gas gen er a tion in car bon if er ous source rocks of the variscan

Annales Societatis Geologorum Poloniae (2013), vol. 83: 353–383.

GAS GEN ER A TION IN CAR BON IF ER OUS SOURCE ROCKS OF THE VARISCAN FORE LAND BA SIN: IM PLI CA TIONS FOR A CHARGEHIS TORY OF ROTLIEGEND DE POS ITS WITH NATURAL GASES

Dariusz BOTOR, Bartosz PAPIERNIK, Tomasz MAÆKOWSKI, Beata REICHER,Pawe³ KOSAKOWSKI, Grzegorz MACHOWSKI & Wojciech GÓRECKI

AGH Uni ver sity of Sci ence and Tech nol ogy, Fac ulty of Ge ol ogy, Geo phys ics and En vi ron mental Pro tec tion,Al. Mickiewicza 30, 30-059 Krakow, Po land, e-mails: [email protected], [email protected],

[email protected], [email protected], [email protected], [email protected], [email protected]

Botor, D., Papiernik, B., Maækowski, T., Reicher, B., Kosakowski, P., Machowski, G. & Górecki, W., 2013. Gasgen er a tion in Car bon if er ous source rocks of the Variscan fore land ba sin: im pli ca tions for a charge his tory ofRotliegend de pos its with natural gases. Annales Societatis Geologorum Poloniae, 83: 353–383.

Ab stract: Nu mer i cal mod el ling of the Car bon if er ous–Perm ian pe tro leum sys tem in the Pol ish Ba sin was car riedout us ing PetroMod soft ware. The Car bon if er ous source rocks con tain or ganic mat ter mostly of a humic na ture(gas-prone Type III kerogen). Subordinately, only in the Lower Car bon if er ous de pos its, kerogen of al gal ma rineor i gin and mixed Type II/III kerogen oc cur. The quan tity of dis persed or ganic mat ter is vari able, but usu ally be low 2% TOC. In the Car bon if er ous sec tion, a pro gres sive in crease in the ma tu rity of or ganic mat ter with depth wasob served, from ap prox i mately 0.5% Rr at the top of the Westphalian in mar ginal parts of the Car bon if er ous ba sinto over 5.0% Rr at the bot tom of the Lower Car bon if er ous in the east ern Fore-Sudetic Homocline. The thermo-genic gen er a tion of hy dro car bons con tin ued from the late Westphalian (east ern Fore-Sudetic Homocline andpartly Pomerania) through out the Me so zoic, up to the Late Cre ta ceous. The ad vance ment of this pro cess is va-ri able in dif fer ent parts of the Car bon if er ous ba sin, reach ing up to 100% of kerogen trans for ma tion in the zones ofmax i mum ma tu rity of or ganic mat ter. How ever, the most in ten sive pe ri ods of gas gen er a tion and mi gra tion werethe Late Tri as sic and the Late Ju ras sic. The most pro spec tive ar eas are lo cated NE of Poznañ–Kalisz line and SWof Poznañ.

Key words: Po land, Pol ish Ba sin, or ganic mat ter, hy dro car bon po ten tial, pe tro leum source rock, ma tu ritymod el ling, gas gen er a tion.

Manu script re ceived 29 August 2013, ac cepted 27 December 2013

IN TRO DUC TION

The Rotliegend ba sin, ex tend ing from the UK to Po land (Kiersnowski et al., 1995; Doornenball and Stevenson,2010; Gast et al., 2010), has sig nif i cant hy dro car bon po ten -tial with vast hy dro car bon re serves, prob a bly still not found, par tic u larly in Po land (e.g., Karnkowski, 2007; Górecki,2008; Burzewski et al., 2009; Pletsch et al., 2010; Botor,2012a). There fore, the Rotliegend ba sin is a ma jor ex plo ra -tion tar get in Po land (Karnkowski, 2007). By even con ser -va tive es ti mates, the hy dro car bons ca pac ity of the Pol ishRotliegend ba sin is con sid ered to ex ceed by far the amountof gas dis cov ered to date (Burzewski et al., 2009). Thus far,only 120×109 m3 of re cov er able gas re serves were found,whilst the un dis cov ered hy dro car bon po ten tial was determi- ned to be in the or der of 1490×109 m3 of gas (Burzewski etal., 2009). Dur ing the fifty years of re search and pe tro leumex plo ra tion in the Rotliegend ba sin of west ern Po land, over80 gas fields have been found (Karnkowski, 1999, 2007).

The Car bon if er ous–Perm ian pe tro leum sys tem in thePol ish Ba sin in cludes the Tournasian to Westphalian (?)source rocks of the Variscan fore land ba sin (Fig. 1), as wellas the res er voir (Rotliegend, Zechstein Lime stone Ca1) andseal (mainly Zechstein evaporites) rocks of the suc ceed ingPermo-Me so zoic Pol ish Ba sin (Pletsch et al., 2010). In thispa per, the re sults of 1-D hy dro car bon gen er a tion mod el lingand 3-D gas mi gra tion mod el ling are pre sented to getherwith the re sult ing re gional maps of kerogen trans for ma tionra tio and gas mi gra tion. They col lec tively ex plain the ma jorfac tors, in flu enc ing the charge his tory of the Pol ish Rotlie-gend gas res er voirs. The tim ing and mag ni tude of gas gen -er a tion in the Car bon if er ous rocks stud ied are ex tremely im -por tant for an un der stand ing of trap for ma tion and fill ing inRotliegend res er voirs. Be cause pe tro leum gen er a tion andex pul sion in the Car bon if er ous sed i ments of the Lublin Ba -sin were de scribed by Botor et al. (2002b), Botor and Littke

(2003) and Karnkowski (2003), this pa per fo cus ses on theCar bon if er ous Variscan fore land ba sin, from the Fore-Sude-tic Homocline to Pomerania and cen tral Po land (Kujawy).

GEO LOG I CAL SET TING

The Permo-Me so zoic Pol ish Ba sin ex tends be tween the Sudetes at the edge of the Variscan interdnides to the southand the Bal tic Sea to the north. The Me so zoic rocks are un -con form ably over lain in that area by a Caino zo ic sed i men -tary suc ces sion, up to 350 m thick. The thick ness of thePermo-Me so zoic strata grad u ally in creases to wards thenorth from about 1 km near the Sudetes to about 8 km in thecen tre of the NE–SW trending Mid-Pol ish Trough (MPT),an elon gated depocentre which par al lels the Teisseyre–Tornquist Zone. The MPT was in verted into the Mid-Pol ishAnticlinorium at the end of Cre ta ceous by a Lara mide com-pressional event. At the same time, the SW part of the Pol -

ish Ba sin was tilted in re sponse to the Lara mide com pres -sion and si mul ta neous up lift of the Bo he mian Mas sif toform the Fore-Sudetic Homocline (FSH), with strata dipp-ping to the NE at the low an gle of a few de grees. The sub -stra tum of the Permo-Me so zoic Pol ish Ba sin is formed bythe thick Car bon if er ous clastic suc ces sion of the Variscanfore land ba sin (Fig. 1; e.g., Mazur et al., 2006a, 2010). Theero sional top sur face of the Car bon if er ous at the base of thePol ish Ba sin plunges be low the Permo-Me so zoic strata andbecomes in ac ces si ble to drill ing in the north ern FSH andMPT.

The Car bon if er ous sed i men tary suc ces sion in west ernPo land con sists of clastic ma rine sed i men tary rocks, lo callyde formed be fore the Perm ian (¯elichowski, 1964; Gro-cholski, 1975; Wierzchowska-Kicu³owa, 1984; Po¿aryskiet al., 1992). The thick ness of the Car bon if er ous sed i mentspen e trated by wells (e.g., Siciny IG-1 well) is a min i mum of 2,500 m of mo not o nous Viséan to Namurian turbidites thatare lo cally capped by Westphalian to Stephanian shal low-

354 D. BOTOR ET AL.

Fig. 1. Main el e ments of Car bon if er ous–Perm ian pe tro leum sys tem in Pol ish Ba sin (based on Reicher, 2008): Car bon if er ous subcrop(source rocks), Rotliegend (res er voir rocks), and Zechtein (seal rock). Ex tent of Early and Late Car bon if er ous based on Pokorski (2008)

wa ter sed i ments (¯elichowski, 1980; Witkowski and ¯eli-chowski, 1981). Fur ther away from the Variscan internides,in Pomerania, the Holy Cross Mts, and the Up per SilesianBlock, the Car bon if er ous clastic suc ces sion trans gress upon the Up per De vo nian car bon ate plat form. In these ar eas, theLower Car bon if er ous is rep re sented by shal low ma rine,mostly car bon ate and clayey rocks, suc ceeded by Namurianand/or Westphalian clastic sed i ments (¯elichowski, 1995;Zdanowski and ¯akowa, 1995). In the Lublin Trough, on-lap ping the East Eu ro pean Craton, the Car bon if er ous suce-ssion com menced in the up per most Viséan and was laiddown di rectly upon De vo nian bed rock (¯elichowski, 1995).

Fur ther de tails on the Car bon if er ous ba sin are given inthe mono graph by Zdanowski and ¯akowa (1995). Re -cently, the De vo nian–Car bon if er ous evo lu tion of the areawas de scribed by Narkiewicz (2007) and Mazur et al.(2006a, b, 2010), whereas the Perm ian to Caino zo ic de vel -op ment of the Pol ish Ba sin was sum ma rized by Mazur et al.(2005), Kiersnowski and Buniak (2006) and Krzywiec(2006a, b). The or i gin and pe tro leum ge ol ogy of the Rotlie-gend ba sin were dis cussed by Karnkowski (1999, 2007).The geo log i cal his tory of the area stud ied is briefly out linedbe low with a fo cus on as pects, rel e vant to the mod el lingstudy by the pres ent au thors.

SUM MARY OF GEO LOG I CALEVO LU TION

Variscan evo lu tion

The sed i men tary and tec tonic his tory of the east ern most Variscides is rel a tively well-un der stood af ter de cades ofgeo log i cal in ves ti ga tions and re cently was sum ma rized byMazur et al. (2006) and McCann et al. (2006). The dis talparts of the Car bon if er ous ba sin were de pos ited upon aMid dle to Late De vo nian car bon ate plat form that oc cu piedthe south ern sec tion of the Laurusian pas sive mar gin. In Po -land, the Laurusian shelf ex tended from Pomerania in theNW, through the Holy Cross Moun tains into the Up perSilesian Block and the Moravo-Silesian do main in the SE.At the end of De vo nian, the plat form was seg mented byfaults and drowned by a ma rine trans gres sion, but its dis talparts per sisted into the Viséan. In the deeper parts of the ba -sin, car bon ates were capped by pe lagic shales, pass ing up -ward into flysch-type Culm sed i ments. Dur ing the Viséan,the Car bon if er ous ba sin sub sided rap idly in re sponse tothrust-load ing, caused by an ad vanc ing Variscan orogenicwedge. Con se quently, in the prox i mal parts of the evolv ingfore land ba sin, thick Viséan to Namurian turbiditic sequen-ces were de pos ited. Sub si dence of the Variscan fore land ba -sin in front of the de vel op ing orogen was as so ci ated with arapid N- and NE-ward ad vance of late-orogenic clastic sys -tems across Wielkopolska and Up per Silesia and Ma³o-polska; it fi nally reached the Lublin Trough in the east andPomerania in the north (Fig. 1). In the dis tal parts of theCarboniferous ba sin, sed i men ta tion was halted lo cally inthe late Namurian and ear li est Westphalian. Af ter a tran -sient pe riod of non-de po si tion, sed i men ta tion re sumed dur -ing the Westphalian A to B. De vel op ment of such a hi a tus,e.g. in north ern Pomerania, is thought to have been caused

by late-orogenic com pres sion, trans ferred from the Varis-can orogenic wedge to its fore land (Ziegler et al., 2002).The en su ing compressional stresses grad u ally changed their di rec tion dur ing the Westphalian and early Stephanian from north to north-east (Narkiewicz, 2007). De spite the in creas -ing body of data, the trace of the Variscan de for ma tion front is still ill-de fined in west ern and cen tral Po land (Jubitz etal., 1986; Po¿aryski et al., 1992), ow ing to only lo cal de vel -op ment of Late Car bon if er ous de for ma tion, poor seis micim ag ing of the sub-salt suc ces sion and the scar city of bore -hole data.

The compressional event, mark ing the end of the Varis- can Orog eny, was fol lowed by a Stephanian to Early Perm -ian tectono-mag matic cy cle (Ziegler, 1990; Benek et al.,1996). At the bound ary of the Stephanian and Autunian(~302–293 Ma; Breitkreuz et al., 2007), in tense magmatism de vel oped in NE Ger many (up to 2000 m of vol ca nic rocks)and NW Po land (e.g., Benek et al., 1996). In Po land, it isrep re sented by a few hun dred metres of volcanogenic rocks(par tic u larly well de vel oped in the Szczecin Trough) thatgrad u ally thin out to wards the east.

Post-Variscan his tory

The out line of the post-Variscan his tory of west ern andcen tral Po land was pro vided by, for ex am ple, Mazur et al.(2005) and McCann et al. (2006). The Pol ish Ba sin was ini -ti ated at the be gin ning of the Perm ian, ow ing to a rift ingevent fol low ing the ces sa tion of the Variscan orog eny. Theba sin com prises a suc ces sion of siliciclastics, car bon atesand thick Zechstein evaporites, sev eral kilo metres thick.The to tal thick ness of the Perm ian to Caino zo ic sed i mentsreaches 8 km, with a NW–SE ori ented depocentre in theMPT (Ziegler, 1990; Dadlez et al., 1998; Van Wees et al.,2000; Stephenson et al., 2003). In the Pol ish Ba sin, a rift ingstage at the bound ary be tween the Car bon if er ous and the Per- mian was as so ci ated with wide spread mag matic ac tiv ity andthe em place ment of vol ca nic rocks, the amount of which in -creases west wards. A post-rift ther mal sub si dence phasecommenced al ready in the Early Perm ian time, as man i festedby the de po si tion of thick non-ma rine Rotliegend clastics.The suc ces sive trans gres sions by a shal low Zechstein seabrought about the sed i men ta tion of up to 2 km of Up per Per-mian evaporites (e.g., Dadlez et al., 1995, 1998; Kiersnow-ski et al., 1995; Benek et al., 1996; Wag ner, 1998; Ste-phenson et al., 2003). Fur ther more, ther mal sub si dencecon tin ued from the Late Perm ian through out the Me so zoicun til the Late Cre ta ceous. The sub si dence rate was vari ablein time, with three dis tinct pulses of ac cel er ated sub si dencein Zechstein to Scythian time, from the Oxfordian to theKimmeridgian, as well as in the early Cenomanian (Dadlezet al., 1995; Stephenson et al., 2003). Re gard less of evolv -ing extensional stresses that were ex erted on the Pol ish Ba -sin, the main depocentre was con sis tently lo cated in theMPT, fol low ing the NW–SE struc tural grain. Some mod i fi -ca tions of the sub si dence pat tern were only re lated to saltmove ments that were ini ti ated in the Early Tri as sic (Dadlez, 2003; Krzywiec, 2004). The sed i men tary suc ces sion of thePol ish Ba sin is sub di vided by sev eral ero sional ep i sodes,no ta bly dur ing the Late Tri as sic, the early/Mid dle Ju ras sic

GAS GEN ER A TION IN CAR BON IF ER OUS SOURCE ROCKS 355

and the Late Ju ras sic/Early Cre ta ceous (Marek and Pajch-lowa, 1997). The pres ently ob served depositional ar chi tec -ture of the Pol ish Ba sin was shaped not only by Permo-Me -so zoic extensional tec ton ics, but also by sub se quent ba sinin ver sion in the Late Cre ta ceous and Palaeo cene (Krzywiec, 2002).

A change of stress re gime in the Pol ish Ba sin was ini ti -ated in the Late Cre ta ceous, prob a bly from the end of theTuronian and was ini tially man i fested by the re ver sal offault ki ne mat ics (e.g., Dadlez et al., 1995; Poprawa, 1997;Lamarche et al., 2003; Stephenson et al., 2003; Mazur et al., 2005; Krzywiec, 2006a, b). Sub se quently, in ver sion led touplift of the ax ial part of the MPT and its sub se quent ero sion.There fore, the MPT, still com pris ing the thick est Permo-Me -so zoic sed i ments, pres ently is trans formed into the Mid-Pol -ish Swell that de fines a re gional anticlinorium. Fur ther more,the sed i ments up lifted in the ax ial part of the Mid-Pol ishSwell were eroded from the top of the Cre ta ceous down tothe Lower Ju ras sic and lo cally to the Up per Tri as sic. TheMe so zoic sed i men tary se quence is uncomformably cov eredby Caino zo ic sed i ments, up to 350 m thick (Piwocki, 2004).

CAR BON IF ER OUS SOURCE ROCKSIN THE STUDY AREA

It is widely ac cepted that the gases ac cu mu lated in theRotliegend res er voirs were de rived from Car bon if er oussource rocks (e.g., Kotarba et al., 1992, 1999, 2004, 2005;Karnkowski, 1999). Anal y ses of the el e men tal and iso to piccom po si tions of the Rotliegend gases, to gether with in ves ti -ga tions of the or ganic mat ter in the Car bon if er ous sed i -ments, in di cated that the gas ac cu mu la tions of the Fore-Su-detic Homocline (Fig. 2) and Pomerania (Fig. 3) are ge net i -cally re lated to hy dro car bon sources, oc cur ring in the Car -bon if er ous source rocks (Kotarba et al., 1992, 1999, 2004,2005; Lokhorst, 1997). How ever, the Pol ish part of theRotliegend Ba sin is not fully com pa ra ble to the West Eu ro -pean part, where Westphalian coals are the main sourcerock for Car bon if er ous and Perm ian gas ac cu mu la tions(Pletsch et al., 2010; Botor, 2012a). Be cause of the ex ten -sive Permo-Me so zoic cover in west ern-cen tral Po land(MPT), it re mains largely un known whether the coal-bear -ing Late Car bon if er ous molasse is pres ent in that area.How ever, with out tak ing the Westphalian coals into ac -count, the amount of dis persed or ganic mat ter con tained inthe Up per and the Lower Car bon if er ous sed i ments that form the sub stra tum of the Rotliegend Ba sin (Fig. 1), is highenough to pro vide a source for the gas, doc u mented inborehole data from the shal lower parts of the Pol ish Ba sin.

Pomerania

Tournaisian, Viséan and Westphalian black shales arethe main source rocks across Pomerania (Figs 4A, 5A).Their hy dro car bon po ten tial (S1 + S2) is fair to ex cel lent,particularly in the case of the Lower Car bon if er ous sed i -ments (Fig. 5A). Thin Westphalian bi tu mi nous coal streaksand interbeds also oc cur in that area and usu ally are lessthan 0.5 m thick (Matyasik, 1998; Kotarba et al., 2004;

Grotek, 2005, 2006; Kosakowski et al., 2006; Matyja, 2006; Pletsch et al., 2010). The Tournaisian and Viséan shalescontain 1.5% and 1.1% TOC on av er age, with max imaaround 10.7% and 4%, re spec tively (Pletsch et al., 2010).Westphalian shales typ i cally con tain 0.3% TOC, up to amax i mum value of 2.7% (Bachleda-Curuœ et al., 1996;Burzewski et al., 1998; Matyasik, 1998; Kotarba et al.,2004, 2005; Grotek, 2005, 2006; Kosakowski et al., 2006;Bahranowski et al., 2007; Pletsch et al., 2010). The kerogen in the rocks is a mix ture of gas-prone Type III and Type II(Fig. 4A). Av er age hy dro gen in di ces (HI) de crease up wards from the Lower Car bon if er ous (550 mg) to the Up per Car -bon if er ous (50 mg), but vari a tion is typ i cally very wide(Fig. 4A). Al though HI val ues for the Lower Car bon if er ousde pos its in Pomerania dem on strate wide vari abil ity (20–550), their av er age be tween 160–200 slightly ex ceeds theme dian for all Car bon if er ous sam ples (110 in sum) (Ba-chleda-Curuœ et al., 1996; Burzewski et al., 1998; Ma-tyasik, 1998; Kotarba et al., 1999, 2004, 2005; Pletsch etal., 2010). Sub or di nate kerogen of al gal or i gin (Type IIkerogen) and mixed Type II/III kerogen oc cur only in theLower Car bon if er ous de pos its. The Lower Car bon if er ousclayey-marly S¹polno For ma tion (of the la goonal andslope-to-ba sin fa cies) con tains con sid er able amounts of oil-prone sapropelic organo-min eral as so ci a tions with liptinite(Type II kerogen) (Kotarba et al., 1999, 2004, 2005;Grotek, 2005, 2006; Bahranowski et al., 2007). How ever,the Car bon if er ous kerogen, has a low hy dro gen con tent, in -di cat ing its rather gas-prone char ac ter (Kotarba et al., 2004;Pletsch et al., 2010). This fact es tab lishes the na ture of theCar bon if er ous or ganic mat ter as a source of gas eous hy dro -car bons (Botor et al., 2002b; Pletsch et al., 2010). The pro -por tion of sta ble iso topes of car bon in nat u ral gas from theRotliegend sam ples con firms a ma jor con tri bu tion fromCarboniferous or ganic mat ter with type III kerogen (Ko-tarba et al., 2004, 2005). Both Rock-Eval Tmax (408 to454°C; Fig. 4A) and vitrinite reflectance val ues (~0.4–1.0% Rr) in di cate that the Car bon if er ous source rocks for themost part are mar gin ally ma ture to ma ture. Only kerogen inthe south ern part of Pomerania shows the high est pres -ent-day ma tu rity of up to 1.9% Rr, in di cat ing the gas-gen er -at ing po ten tial of the Car bon if er ous in this area (Pletsch etal., 2010).

Fore-Sudetic Homocline

In the Fore-Sudetic Homocline (FSH), Car bon if er oussource rocks are mainly shales with dis persed or ganic mat -ter. Their hy dro car bon po ten tial (S1 + S2) var ies from poorto very good (Fig. 5B). The or ganic car bon con tent is gen er -ally lower than in the other parts of the Pol ish Ba sin andranges from 0.5 to 2%, but rarely reaches 4% (Fig. 5B)(Nowak, 2003, 2007; Pletsch et al., 2010; Poprawa, 2010;).The or ganic mat ter dis persed in the Car bon if er ous sourcerocks is prin ci pally of humic char ac ter (gas-prone Type IIIkerogen), but highly ma ture or overmature (Fig. 4B; No-wak, 2003, 2007; Pletsch et al., 2010; Poprawa, 2010). Theor ganic mat ter mainly con sists of vitrinite group macerals,with sub or di nate macerals of the inertinite and liptinitegroups. Lesser quan ti ties of oil-prone and mixed II/III Type

356 D. BOTOR ET AL.


.2 .giF

rca noi tces-ssorc cita mehc

S

hcstelP ;6002 ,ikceró

G re tfa dei f idom ;devo

mer noi tces c io zoniaC( enilco

moH citedu

S-eroF sso

.la te)0102 ,

kerogen have been found in LowerCarboniferous sed i ments (Nowak,2003, 2007; Pletsch et al., 2010; Po-prawa, 2010). How ever, a re li able cha- racterisation of the orig i nal kerogen isse verely ham pered, ow ing to the highmaturity of most samples col lectedfrom the area (Dembicki, 2009). Ingen eral, Car bon if er ous source rocks inthe Fore-Sudetic Homocline are over-ma ture over wide ar eas, be cause ofdeep burial, Early Perm ian magmatism and hy dro ther mal ac tiv ity (Maækow-ski, 2005; Poprawa et al., 2005). Thema tu rity in creases in two di rec tions,to wards the ax ial part of the MPT andthe east ern part of the FSH. Tmax val -ues range from 440 to 520°C (Fig. 5B)and vitrinite reflectance from 1.0 to5.0% (Karnkowski, 1999; Wag ner,1999; Nowak, 2003, 2007; Poprawa etal., 2005; Grotek, 2006; Maækowski etal., 2008; Pletsch et al., 2010; Popra-wa, 2010). How ever, in the vi cin ity ofthe gas fields the ma tu rity is in therange of 0.7 to 2.0% Rr.

Kujawy–Masovia

In the Kujawy–Masovia area, only a few wells pen e trated the Car bon if er -ous strata, be cause of the deep burialand the amount of data on the qual ityof the source rocks is lim ited (Fig. 4Cand 5C). Most sam ples come from thewells lo cated near War saw (Korabie-wice PIG1, Mszczonów IG1, Nada-rzyn IG1). The hy dro car bon po ten tial(S1 + S2) is very vari able from poor toexellent (Fig. 5C). The or ganic car boncon tent ranges from 0.3 to 15%, but insome sam ples reaches ~80%, ow ing tothe oc cur rence of coal streaks and in-terbeds (Fig. 5C) (Matyasik, 1998; Bo- tor et al., 2002b; Pletsch et al., 2010).The kerogen is a mix ture of gas-proneType III and Type II (Fig. 4C). In theWestphalian sam ples, humic or ganicmat ter (Type III) dom i nates (Fig. 4C).Hy dro gen in di ces val ues for the Car-boniferous or ganic mat ter dem on strate a wide scat ter (11– 620), but their meanvalue is around 160 (Fig. 4C). Rock-Eval Tmax (420 to 455°C; Fig. 4C) andvitrinite reflectance in the range ~0.7–1.0% (Koz³owska and Poprawa, 2004)show that the Car bon if er ous or ganicmat ter is mar gin ally ma ture to ma ture(Pletsch et al., 2010).

358 D. BOTOR ET AL.

.3 .giF

hcstelP ;8002 ,ikceró

G re tfa dei f ido

m ;devo mer noi tces c io zonia

C( ainaremo

P ssorca noi tces-ssorc cita mehc

S

.la te)0102 ,

RES ER VOIR ROCKS AND GAS DE POS ITS

The Car bon if er ous–Perm ian pe tro leum sys tem in thePol ish Ba sin com prises res er voirs of vari able age and li thol -ogy (Fig. 6), be long ing to two sep a rate pe tro leum provin-ces, Pomerania and Wielkopolska (Fore-Sudetic Homo-cline) in the north and south, re spec tively (Niedbalec andRadecki, 2007). The re gional seal is mainly Zechstein eva-porites and par tially Rotliegend claystone (Fig. 1). The traps are both struc tural and strati graphic, but are usu ally smalland of ten ac com pa nied by faults (Pletsch et al., 2010).

Nat u ral gas in the Pom er a nian res er voirs is rich in ni tro -gen (40–78%) and con tains 22 to 58% of meth ane, someeth ane, pro pane and he lium. The ni tro gen con tent in creaseswest wards and less ob vi ously to the south. The com po si tion

of nat u ral gas in the FSH is di verse. North of the Wolsztyn-Pogorzela High, it is mostly meth ane (70–90%) with ad mix -tures of ni tro gen (<25%), higher hy dro car bons (<2%), CO2

(<2%) and traces of he lium. The gas qual ity de creases south -wards from the Wolsztyn-Pogorzela High, where fields con -tain 16–80% of meth ane, 20–80% of ni tro gen, sim i lar CO2

and higher hy dro car bon con tents, but with in creased he liumcon cen tra tions of up to 0.6% (Lokhorst, 1997; Pletsch et al.,2010).

Pomerania

The old est res er voir unit is rep re sented by faulted Car -bon if er ous strata. Small struc tural and strati graphic trapswere dis cov ered in the Visean lime stones (po ros ity 2–16%,


Fig. 4. Rock Eval Hy dro gen In dex ver sus tem per a ture Tmax for Car bon if er ous strata in (A) Pomerania, (B) Fore-Sudetic Homoclineand (C) Masovia–Lublin area. Ge netic curves for kerogen from Espitalié et al. (1985). Data mod i fied af ter Bachleda-Curuœ et al. (1996),Burzewski et al. (1998), Matyasik (1998), Nowak (2003), Kotarba et al. (1999, 2004, 2005), Kosakowski et al. (2006), Pletsch et al.(2010), and Poprawa (2010)

per me abil ity 100–400 mD), Namurian (po ros ity 16–23%;per me abil ity: up to 270 mD), and Westphalian (po ros ity 5–15%; per me abil ity up to 190 mD). In the Rotliegend, all butone con ven tional gas ac cu mu la tion were dis cov ered at thetop of the ae olian sand stones, both in the Pomerania andWielkopolska pe tro leum prov inces. In Pomerania, the thic-kness of the ae olian sand stones rarely ex ceeds 50 m, whileflu vial sand stones are of ten up to 750 m thick. The Rot-liegend suc ces sion con tains a num ber of po ten tial res er voirs in flu vial and playa sed i ments (Papiernik et al., 2010),which can con tain con ven tional or tight gas. Both the flu vial and ae olian sand stones have fair po ros i ties (0–13%, gen er -ally <5%), but their permeabilities re main mostly less than 1 mD (Pletsch et al., 2010). There fore, only eleven Car bon if -er ous-sourced con ven tional gasfields have been proven inPomerania (Pletsch et al., 2010).


Since the Lower Car bon if er ous rocks of the FSH are

rather poor res er voirs, only the Paproæ C con ven tional gasac cu mu la tion was dis cov ered there (Karnkowski, 1999).How ever, con sid er able tight gas ac cu mu la tions are expec-ted in the base ment of the FSH (Poprawa and Kiersnowski,2008, 2010). This as sump tion was re cently sub stan ti ated byprom is ing re sults from the Siciny-2 test well (San Leon,2013). The most im por tant res er voir unit of the FSH, as inPomerania, is the Up per Rotliegend (Fig. 6). It con sists ofsandy-shaly sed i ments, rep re sent ing three main desert de-po si tional sys tems: ae olian (dune and interdune en vi ron -ments), flu vial (com pris ing flu vial chan nels and al lu vialfans) and playa (Kiersnowski, 1997; Jarzyna et al., 2009).Their spa tial dis tri bu tion and vari able thick ness re flect de -po si tion within an asym met ric con ti nen tal half-graben(Kiersnowski, 1998; Pokorski, 1998).

On the ba sis of its res er voir rocks and gas com po si tion,the Fore-Sudetic Homocline is sub di vided into 3 re gionsthat cor re spond to the Wolsztyn-Pogorzela High and the ar -eas to the north and south of it. Thirty-eight gasfields oc curin the up per most Rotliegend sand stones north of the Wolsz-

360 D. BOTOR ET AL.

Fig. 5. Pe tro leum source qual ity di a gram for Car bon if er ous strata in (A) Pomerania, (B) Fore-Sudetic Homocline and (C) Masovia–Lublin area. Clas si fi ca tion af ter Hunt (1979) and Pe ters and Cassa (2002). Data mod i fied af ter Bachleda-Curuœ et al. (1996), Burzewski etal. (1998), Matyasik (1998), Nowak (2003), Kotarba et al. (1999, 2004, 2005), Kosakowski et al. (2006), Pletsch et al. (2010), andPoprawa (2010)

tyn-Pogorzela High. In that area, the res er voir sand stonesdisplay po ros i ties rang ing from 0 to >20%, (on av er age12%), ir reg u larly but con sis tently de creas ing with depth(Papiernik et al., 2008; Papiernik et al., 2010). The per me -abil ity of ae olian sand stones is over 100 mD close to theWolsztyn-Pogorzela High, but de creases to slightly morethan 1 mD far ther north (Papiernik et al., 2008).

The sec ond re gion is sit u ated to the S and SW of theWolsztyn-Pogorzela High, where over 30 gasfields werefound in the up per most Rotliegend sand stones, in the Zech-stein Lime stone, or com monly in both (Fig. 6; Papiernik etal., 2008). The gas-bear ing ae olian sand stones dis play ex -cel lent po ros ity, fre quently ex ceed ing 30% (on av er age15%) and fairly good per me abil ity, rang ing from a few tohun dreds of millidarcies (me dian on av er age in pro duc tivein ter vals ~10 mD; Papiernik et al., 2010, 2012). In the sou-thernmost part of the FSH, shal low ma rine car bon ate plat -form and oolitic bar ri ers are re flected in grainstones, bound- stones, packstones, as well as mudstones and wackestones

in the zones of lower en ergy (Papiernik et al., 2008; S³o-wakiewicz and Miko³ajewski, 2011). The car bon ates dis -play po ros i ties of 0–34% (av er age 6.3%) and permeabilities of 0–~500 mD (av er age 12.9 mD), while in the oolitic bar ri -ers the po ros i ties are 0–34% (av er age 5.5%) and perme-abil i ties 0–190 mD (av er age 6.8 mD). The most ex ten sivelyde vel oped open ma rine sed i ments, dom i nated by mudstones and wackestones, dis play very poor res er voir prop er ties.

The third re gion is the Wolsztyn-Pogorzela High, rep -re sent ing a pre-Perm ian ridge, where the Rotliegend res er -voir sand stones are ab sent and the Zechstein strata di rectlyover lie Car bon if er ous sed i ments and pre-Car bon if er ousmetamorphic rocks. There are six gasfields in the ZechsteinLime stone of the Werra cyclothem on the Wolsztyn-Pogo-rzela High. They were found in mas sive reef struc tures, inthe vi cin ity of Koœcian. The po ros i ties of these rocks are upto 45% (av er age ~15%) and the max i mum per me abil itymore than 1000 mD.


Fig. 6. Lo ca tion map of Rotliegend res er voirs and Zechstein Lime stone (Ca1) in the light of res er voir fa cies dis tri bu tion (mod i fied af -ter Papiernik et al., 2008)

METH ODS AND DATA

A to tal of 120 1-D mod els was con structed, us ing thePetroMod soft ware (Schlumberger, 2013a), in clud ing 52for wells and 68 for pseudo-wells. Gas mi gra tion anal y siswas car ried out, us ing the PetroMod 3D flowpath mod el ling soft ware (Schlumberger, 2013a). The most im por tant re -sults were shown on re gional maps of heat flow, erodedoverbur den, kerogen trans for ma tion ra tio and gas mi gra -tion. The ba sic char ac ter is tics of the burial and ther mal his -tory, as well as the gas gen er a tion his tory of se lected wells,are also pro vided. All maps were cre ated by means of thePE TREL soft ware (Schlumberger, 2013b).

Ba sin mod el ling tech nique

Nu mer i cal mod el ling tech niques per mit the sim u la tionof the com plex set of in ter act ing phys i cal and chem i cal pro -cesses, tak ing place dur ing the evo lu tion of a sed i men taryba sin. A start ing point for the mod el ling ex er cise is a con -cep tual model (Waples et al., 1992; Poelchau et al., 1997;Yalcin et al., 1997), which de scribes the geo log i cal evo lu -tion of the study area, in clud ing geo log i cal, geo phys i cal and geo chem i cal data. A discretized nu mer i cal model, which re- pres ents the con cep tual model, is then used for sim u la tionpur poses (Yalcin et al., 1997).

The geo log i cal his tory of a spe cific lo ca tion, e.g. a sin -gle bore hole or a so-called pseudo-well (Poelchau et al.,1997), is cal cu lated by the fi nite dif fer ence method. A mod -el ling frame work of the con cep tual model is built in thetime di men sion. Geo log i cal events, scaled in time, cre atethe frame work of a model and gov ern the data in put. Thedata set for each event con sists of du ra tion, depositional orero sional thick ness, li thol ogy, bathymetry, sed i ment/wa terin ter face or sur face tem per a ture, and heat flow. Petrophy-sical pa ram e ters, such as po ros ity, den sity, ther mal con duc -tiv ity, etc., are then de fined on the ba sis of li thol ogy. Af tereach sim u la tion run, the cal cu lated re sults have to be com -pared with the mea sured val ues, in or der to cal i brate themodel and check its geo log i cal re li abil ity. Ma jor cal i bra tion pa ram e ters are re cent bore hole tem per a tures, mean ran domval ues of vitrinite reflectance and Rock-Eval ma tu rity in di -ces. Cal i bra tion is usu ally per formed by vary ing the palaeo-heat flow or the orig i nal thick ness of the now eroded sed i -men tary units within geo log i cally rea son able lim its (Wy-grala, 1989; Waples et al., 1992; Yalcin et al., 1997).

Ini tially, heat flow es ti mates for the past stages of ba sinhis tory are as signed on the ba sis of tec tonic set ting (Yalcinet al., 1997). In the fol low ing it er a tions, the palaeo-heat-flow val ues are ad justed through the mod el ling pro ce dure,in or der to achieve the best fit be tween the cal cu lated modeland the mea sured cal i bra tion pa ram e ters. Heat flow val uesare best con strained for times of max i mum tem per a ture,which cor re spond to the max i mum burial in many cases(Waples et al., 1992). Dur ing mod el ling, dif fer ent burial-up lift sce nar ios are tested to find a model, which is best cal i -brated with the ma tu rity val ues mea sured in rock sam ples.Ap pli ca tion of the ki netic EASY %Rr ap proach en ables cal -cu la tion of the mean ran dom vitrinite reflectance up to thevalue 4.6% Rr (Swee ney and Burnham, 1990).

More de tails on the prin ci ples of the mod el ling tech -nique are given in, for ex am ple in Wygrala (1989), Swee -ney and Burnham (1990), Waples et al. (1992), Poelchau etal. (1997), Yalcin et al. (1997), and Hantschel and Kauerauf (2009). In Pol ish, the de tails of ma tu rity mod el ling aregiven in Botor and Kosakowski (2000) and Botor et al.(2002a).

Mod el ling in put data

A set of strati graphic and lith o logic data was com piledfor the wells stud ied within the frame work of a con cep tualmodel of the evo lu tion of the study area. The con cep tualmodel was based on pub lished data and in ter pre ta tions ofthe geo log i cal de vel op ment of the Car bon if er ous Ba sin andits later Perm ian–Caino zo ic evo lu tion. Palaeothickness andpalaeofacies maps of the Perm ian and Me so zoic se quencesand re gional cross-sec tions across the study area were par -tic u larly use ful (Dadlez et al., 1994; Marek and Pajchlowa,1997; Dadlez, 2006). Strati graphic and lith o logic data werealso com piled from pa pers by Burzewski (1984), Wierz-chowska-Kicu³owa (1984), Górecka-Nowak (2007), andNowak (2007).

Pe ri ods of sed i men ta tion and ero sion/non-de po si tion,sed i ment types and thick nesses were iden ti fied for eachwell. Litostratigraphic data for the pseudo-wells were com -piled, on the ba sis of geo log i cal re gional maps and cross-sec tions (Maækowski et al., 2008). The age (in Ma) of stan -dard chronostratigraphic units is given af ter Gradstein et al.(2004). The tim ing of Perm ian vol ca nism was adopted from the geo chron ol ogi cal data by Breitkreuz et al. (2007). Ifnec es sary for mod el ling pur poses, spe cific lithologies, rep -re sent ing the best ap prox i ma tion to dif fer ent sed i men tarypack ages, were as signed to cer tain strati graphic units (in -clud ing eroded in ter vals). Fixed PetroMod lithologies (withpetrophysical prop er ties de ter mined for each rock type)were de fined on the ba sis of de tailed lithological de scrip -tions of the core and cut ting ma te rial in cluded in the doc u -men ta tion of wells. Ther mal con duc tiv ity was com puted,us ing the method de vel oped by Deming and Chap man(1989). Ma trix ther mal con duc tiv ity val ues were spec i fiedfor each li thol ogy and then cal cu lated for mixed lithologies,us ing geo met ric av er ages. Heat flow val ues, used in con -junc tion with each ther mal con duc tiv ity set, were se lected,on the ba sis of the qual ity of the fit be tween the model pre -dic tions and the ac tual ob ser va tions of pres ent-day tem per a -ture-depth and ma tu rity-depth pro files. The pres ent-dayheat flow val ues were in ter po lated from the sur face heatflow maps (Plewa, 1994; Szewczyk and Gientka, 2009).The val ues ob tained range from 40 to 78 mW/m2. Map pingwas based on the lat est avail able geo ther mal data from bore -holes all over the Pol ish Ba sin, care fully ver i fied in or der toex clude un re li able (mostly non-equi lib rium) mea sure ments. Meth od olog i cal prob lems, re lated to heat flow cal cu la tionand map ping, were re cently dis cussed in Szewczyk andGientka (2009). How ever, pres ent-day heat flow val ues donot in flu ence the mat u ra tion his tory of in verted bas ins (likethe Pol ish Ba sin), which is mainly gov erned by palaeo-heatflow in a pre-in ver sion pe riod (Waples et al., 1992; Poel-chau et al., 1997).

362 D. BOTOR ET AL.

Mean ran dom vitrinite reflectance and Rock-EvalTmax mea sure ments were im ple mented in the nu mer i calmod el ling pro ce dure as ma jor pa ram e ters, cal i brat ing theburial and ther mal his tory of the ba sin (e.g. Yalcin et al.,1997; Senglaub et al., 2006). Ther mal ma tu rity val ues in -cluded sev eral sources of data (Bachleda-Curuœ and Se-myrka, 1990; Bachleda-Curuœ et al., 1996; Burzewski et al., 1998; Grotek, 1998, 2005, 2006; Grotek et al., 1998; Ma-tyasik et al., 1998; Wag ner, 1999; Botor et al., 2002b;Nowak, 2003, 2007; Górniak et al., 2004; Kotarba et al.,2004, 2005; Resak et al., 2008).

Ba sic as sump tions

Nu mer i cal mod el ling was car ried out on a re gionalscale for the en tire the Pol ish Ba sin. It was nec es sary to sim -plify sev eral as pects of the con cep tual model and me thod i -cal ap proach, such as the struc tural-thick ness model of theCar bon if er ous and Perm ian to Me so zoic strata or the in flu -ence of salt bod ies. The ini tial petrophysical pa ram e ters ofrocks are de fault val ues of the PetroMod soft ware. Also there con struc tion of sed i ment palaeotemperatures as a func tion of time and depth was based on some as sump tions, since itre quires spec i fi ca tion of heat flow and ther mal con duc tiv ityval ues of the rock col umn. Con se quently, sev eral heat trans -fer as sump tions were used in the mod el ling: (1) heat trans -fer was by con duc tion, (2) steady state ther mal con di tionswere used to model heat flow at the base of sed i men tarysec tion to the sur face, (3) heat was as sumed to come fromthe base ment, but not from ra dio genic heat sources withinthe rocks, (4) the base ment heat in put was not dif fer en ti atedbe tween ra dio genic heat pro duc tion and heat from man tlecon vec tion. Ow ing to the rift ing of the Mid-Pol ish Trough(Dadlez et al., 1995; Karnkowski, 1999; Stephenson et al.,2003; Mazur et al., 2005, 2006) gen er ally higher heat flowval ues than pres ent-day were as sumed for the Perm ian–Early Tri as sic pe riod, which gen er ally dropped down to thepres ent-day val ues.

RE SULTS

Burial and ther mal his tory

The first phase of ba sin mod el ling was the re con struc -tion of the burial and ther mal his tory of the Car bon if er oussource rocks, a pre-req ui site for fur ther pe tro leum gen er a -tion and mi gra tion mod el ling. How ever, since the qual ity ofthe cal i bra tion data is vari able, in many cases the ther malhis tory mod els are not unique (e.g. Majorowicz et al., 1984; Speczik and Koz³owski, 1987; Górecki et al., 1995; Bu-rzewski et al., 1996; Karnkowski, 1996, 1999; Burzewski,1997; Poprawa et al., 2005). The mea sured vitrinite reflec-tance from shal low bore holes in the north ern and cen tralparts of the ba sin in many cases does not per mit unique con -clu sions on the palaeogradient. How ever, it is pos si ble toas sess the firm and weak points in the al ter na tive con ceptsof geo log i cal and ther mal evo lu tion. The lack of bore holes(Fig. 1) with Rr mea sure ments be tween Szczecin – GorzówWielkopolski – Zielona Góra ren ders all re sults in this area(par tic u larly west of these cit ies) some what hy po thet i cal.

The burial and ther mal his tory of the Pol ish Ba sin is rel -a tively well known and the pres ent pa per does not pro videnew data for fur ther cal i bra tion. Ac cord ingly, burial andther mal his tory mod els were adopted in the pres ent 1-D pe -tro leum sys tem mod el ling study from among the best-fitmod els, pub lished by (1) Burzewski et al. (1996, 1998),Resak et al. (2008) for Pomerania, (2) Botor (2011a) forKujawy and the north ern FSH, (3) Poprawa et al. (2002),Koz³owska and Poprawa (2006) for Masovia, and (4) Botor(2012a, b), Botor et al. (2012), Botor (2011b), Poprawa etal. (2005) for the FSH. De tailed dis cus sion of the burial and ther mal his tory, model cal i bra tion and sen si tiv ity anal y siscan be found in the above men tioned pa pers. In the pres entac count, the burial and ther mal his tory is only sum ma risedon a re gional scale in the con text of fur ther gas gen er a tionand mi gra tion mod el ling.

The most im por tant and typ i cal ex am ples of burial andther mal his tory are given in Figs 7, 8. In Pomerania, Car -bon if er ous source rocks were bur ied to depths of 3–6 km.How ever, the depth of burial is vari able across the ba sin. Inthe Pom er a nian Swell re gion, the burial his tory from welldata is mostly char ac ter ized by rel a tively rapid sub si dencefrom the Perm ian to the Tri as sic or the Ju ras sic, fol lowed by less in ten sive sub si dence in the Cre ta ceous (Fig. 7A–C). Inthe Late Cre ta ceous/Palaeogene, a rapid phase of up lift oc -curred. The for mer event marks the on set of the MPT and isas so ci ated with con sid er able crustal ex ten sion (Dadlez etal., 1995). Be tween the Early Tri as sic and Late Cre ta ceous,the area sub sided al most con tin u ously, with only spo radicin sig nif i cant ero sional events, due to salt dom ing in Keupertimes. Af ter the Early Tri as sic, sed i men ta tion rates weremuch lower, par tic u larly in the lat est Tri as sic and Cre ta -ceous. Fi nally, the Late Cre ta ceous/Palaeogene up lift re -sulted in the re moval of 900–1800 m of sed i ments (Fig.7A–C). The best mod el ling re sults (i.e. the best fit be tweenthe mea sured and cal cu lated Rr val ues) were ob tained, as -sum ing a thick ness of eroded Up per Cre ta ceous of 300–700m and heat flow of about 30–50 mW/m2 dur ing this time(Figs 7A–C, 10A). For the Car bon if er ous to Early Tri as sic,the heat flow as signed was around 55–93 mW/m2 (Fig.10B). Higher val ues were adopted, be cause of the as sumedrift ing of the MPT (Dadlez et al., 1995). How ever, it is dif fi -cult to as sess the heat flow evo lu tion for this pe riod, be -cause of ma jor Me so zoic burial, which caused over print ingof the Variscan Rr re sponse. Fur ther de tails of the burial and ther mal his tory are given in Resak et al. (2008) and Bu-rzewski et al. (1998).

In the Kujawy area and the cen tral part of the MPT (Fig. 7D, E), the burial his tory is also char ac ter ised by very rapidsub si dence in the Late Perm ian to Early Tri as sic, fol lowedby slower sub si dence from the Late Tri as sic to the Cre ta -ceous. Fi nally, Me so zoic sub si dence was in ter rupted by theLate Cre ta ceous/Palaeogene up lift, which caused ero sion of vari able amounts, af fect ing the late Me so zoic sec tion (fromnil to c. 3 km in the case of the Budziszewice IG1 well). Inthe best fit mod els, the heat flow for the Byczyna well wasas sumed to be 55 mW/m2 (in the Me so zoic–Caino zo ic), and for the Budziszewice IG1 well, 55 mW/m2 from the LatePerm ian to the Ju ras sic, 40 mW/m2 in the Cre ta ceous, and60 mW/m2 in the Caino zo ic. Ow ing to the ma jor Me so zoic


burial, it is dif fi cult to as sess heat flow (~60–110 mW/m2)for Car bon if er ous to Early Perm ian time (Botor, 2011a).Fur ther de tails of burial and ther mal his tory of this area aregiven in Botor (2011a).

In the Masovia area (Fig. 8A, B), the burial his tory ischar ac ter ized by more or less con tin u ous sub si dence fromthe Car bon if er ous to the end of the Cre ta ceous. An ac cel er a -tion of the sub si dence rate is ob served in the Late Car bon if -

364 D. BOTOR ET AL.

Fig. 7. Ex am ples of se lected mod els: DŸwirzyno-3, Wolin-IG1, Okonek-1, Budziszewice IG1, Byczyna IG-1,

er ous, Late Perm ian to Early Tri as sic, and Late Ju ras sic andLate Cre ta ceous. A ma jor pe riod of up lift and de nu da tionwas in the lat est Car bon if er ous to Early Perm ian, while theLate Cre ta ceous/Palaeogene up lift was not sig nif i cantlymarked in this area. Ther mal his tory mod els for Masovia as -

sume a short-lived hy dro ther mal (?) Ju ras sic event, in or derto achieve the best fit be tween the mea sured and cal cu latedRr that was sug gested by Koz³owska and Poprawa (2004).

In SW Po land, the Car bon if er ous sed i men tary suc ces -sion gen er ally ex ceeds 2,500 m in thick ness and is pre dom i -


Fig. 8. Ex am ples of se lected mod els: Mszczonów-IG2, Korabiewice-PIG1, Kalisz-IG1, Marcinki-IG1, Siciny-IG1

nantly com posed of clastic ma rine sed i men tary rocks,tectonised (folded and thrust-faulted) be fore Perm ian times(Mazur et al., 2006, 2010). The Car bon if er ous sed i mentsare over lain dis cor dantly by the Perm ian and Me so zoic sed -i men tary cover of the Pol ish Ba sin, the south-west ern partof which is re ferred to as Fore-Sudetic Homocline. Ther malma tu rity of the or ganic mat ter in the east ern FSH shows asig nif i cant dif fer ence in vitrinite reflectance val ues be tween the top of the Car bon if er ous suc ces sion and the lower partof the Permo-Me so zoic cover (Fig. 8C; Maækowski, 2005;Poprawa et al., 2005).

The re sults of the 1-D ma tu rity mod el ling clearly in di -cate that Car bon if er ous sed i ments in the east ern part of theFSH at tained their ther mal ma tu rity prior to the Late Perm -ian (Botor et al., 2012). Ow ing to deep burial, and magma-tism (of Early Perm ian age), as well as pos si ble hy dro ther -mal pro cesses, gas source rocks are mostly overmature. Inmost mod els, the best-fit cal i bra tion has been achieved byap ply ing high heat-flow val ues in the Car bon if er ous–EarlyPerm ian pe riod (~90–140 mW/m2; Fig. 10A), and de creas -ing heat flow for the youn ger pe ri ods, suc ces sively drop -ping down to the pres ent-day val ues (Botor, 2011b, 2012a,b; Botor et al., 2012). A pos si ble rea son for the high heatflow in Car bon if er ous–Perm ian time was prob a bly vol ca -nic, as well as hy dro ther mal ac tiv ity in the study area (Karn- kowski, 1999; Poprawa et al., 2005; Maækowski et al.,2008). Burial and ther mal his tory mod els for the FSH showex tremely deep burial and very high heat flow in the Car -bon if er ous (Fig. 8C–E). In the east ern FSH, the great thick -ness of the eroded sec tion in the range of 2–4 km was re con -structed from ma tu rity mod el ling (Fig. 7C, D; Maækowski,2005; Poprawa et al., 2005; Botor, 2011b, 2012a, b; Botoret al., 2012). The Late Perm ian–Me so zoic and Caino zo icburial, as well as mod er ate heat flow (~50–70 mW/m2), didnot change the ma tu rity pro file of the Car bon if er ous sed i -ments in the east ern FSH area (Botor, 2011b, 2012a, b; Bo-tor et al., 2012).

In the cen tral-west ern part of the FSH (the Siciny IG1well area), the burial and ther mal his tory mod els are dif fer -ent from those above men tioned for the east ern FSH area.The ther mal ma tu rity pro files do not show any breaks (as inthe east ern FSH) in vitrinite reflectance val ues be tween thetop of the Car bon if er ous and the lower part of the Permo-Me so zoic (Fig. 8E; Maækowski et al., 2008). There fore, thether mal mat u ra tion of Car bon if er ous or ganic mat ter (andgas gen er a tion) was mainly de vel oped in Me so zoic time(Maækowski et al., 2008; Botor, 2011b, 2012b; Botor et al.,2012). The most im por tant and ob vi ous ev i dence is the oc -cur rence in this area of gas fields (Fig. 1) that would nothave ex isted, if all of the mat u ra tion had been com pleted be -fore the Perm ian, as sug gested by Poprawa et al. (2005).The burial his tory of the strata, pen e trated by the Siciny IG1 well, is char ac ter ised by a pro longed sub si dence dur ing theMe so zoic (Fig. 8E). There were two ma jor pe ri ods of up liftand de nu da tion: (1) in the Late Car bon if er ous to the EarlyPerm ian and (2) in the Late Cre ta ceous/Palaeogene. Thefirst one is dif fi cult to quan tify, ow ing to high burial in theMe so zoic, while the sec ond may have in volved de nu da tionof 1200 m of sed i ments (Fig. 8E). How ever, be cause thereis no break in the Rr pro file and Rr val ues are much smaller

than in the east ern FSH, it seems likely that the burial depthin the Car bon if er ous was not very high (Fig. 8E). The best-fit cal i bra tion was achieved by ap ply ing in creased heat-flow val ues (~95 mW/m2) in the Car bon if er ous–Early Perm ianpe riod. They prob a bly were re lated to the vol ca nic and hy -dro ther mal ac tiv ity in the study area. Late Perm ian–Me so -zoic and Caino zo ic times were char ac ter ised by mod er ateheat flow in the range 50–70 mW/m2 (Fig. 10B; Botor,2011b, 2012b, Botor et al., 2012).

ERO SION

Up to now, the thick ness of eroded over bur den (Car -bon if er ous to Me so zoic) was ana lysed with ref er ence to me -chan i cal com pac tion (only in Pomerania) (Stefaniuk et al.,1996; Dadlez et al., 1997; Maækowski et al., 1998), ap pliedto thick ness trends of the sed i men tary fill (Papiernik andReicher, 1998), and ma tu rity mod el ling (Burzewski et al.,1996, 1998; Karnkowski, 1996, 1999; Poprawa et al., 1997; Koz³owska and Poprawa, 2004; Poprawa et al., 2005;Resak et al., 2008; Botor, 2011a, b; Botor et al., 2012).How ever, the re sults ob tained are not very con sis tent acrossthe ba sin.

The val ues given be low for the ma jor ero sional events,the post-Variscan (Late Car bon if er ous–Early Perm ian) andthe post-Lara mide (Late Cre ta ceous–Palaeogene), are based on es ti mates that al lowed the best-fit cal i bra tion be tweenval ues of mea sured and cal cu lated vitrinite reflectance. Theval ues cal cu lated in 1-D mod els are shown as a map view inFig. 9A, B.


The post-Variscan ero sion var ies from ~700–800 m inthe SW part of the FSH (Siciny IG1 well area) to over 4,000m in the east ern and SE part of the FSH (Kalisz–Dymekarea; Fig. 9A). In the ma jor ity of ar eas, the post-Variscanero sion ranges from 1,000 to 2,500 m. The lower val ues ob -tained from the SW part of FSH are prob a bly re lated to deep Me so zoic burial, which makes quan ti ta tive as sess ment ofthe Variscan ero sion im pos si ble. Post-Lara mide ero sion ismuch less vari able, in creas ing from NE (be low 200 m) toSW (~1,500 m) (Fig. 9B).

Pomerania

The cal cu lated thick ness of the eroded sed i men tary fillaf ter the Late Car bon if er ous (post-Variscan ero sion) is gen -er ally low (~400–800 m) in Pomerania (Fig. 9A), whilst theLate Cre ta ceous/Palaeogene (post-Lara mide) ero sion is va-riable (Fig. 9B). The high est val ues were ob tained in the in -verted part of the Pom er a nian Anticlinorium (~2,000–2,500 m), whereas the val ues are much lower in the Szczecin De -pres sion and the Pom er a nian De pres sion (0–1,000 m).

Kujawy and Masovia

In the area ap prox i mately be tween Pi³a–Bydgoszcz–£ódŸ, the cal cu lated thick ness of eroded Palaeozoic rocks is

366 D. BOTOR ET AL.


Fig. 9. Cal cu lated ero sion: post-Variscan (A), Lara mide (B)

368 D. BOTOR ET AL.

Fig. 10. Palaeo-heat flow: Variscan (A), Cre ta ceous (B)

rel a tively low, usu ally be low 1,000 m (Fig. 9A). The post-Lara mide ero sion is also low (0–200 m) in the area, ex tend -ing from SE of the Pi³a IG1 well to the £ódŸ area (Fig. 9B),whilst to the SE of £ódŸ (to wards the Holy Cross Mts), it isex tremely high (the Budziszewice IG1 well, up to 3 km)(Fig. 9B). In the Masovia area (War saw De pres sion), thecal cu lated thick ness of eroded Palaeozoic rocks is low, gen -er ally in the range of 400–800 m (Fig. 9A). The post-Lara -mide ero sion in Masovia (Korabiewice PIG1 – MszczonówIG1) is also low, at 0–200 m (Fig. 9B).

HEAT FLOW

The val ues of palaeo-heat-flow, pro vided in this studyfor the pe riod from the Car bon if er ous to the Pres ent, are ar -bi trary and based on es ti mates that give the best-fit cal i bra -tion be tween mea sured and mod elled vitrinite reflectances.The val ues of palaeo-heat-flow, cal cu lated in the 1-D mod -els, were used to cre ate the maps in Fig. 10A, B.


In the SE and N parts of the FSH, heat-flow val ues were the high est (above 110 mW/m2) and the low est (~60–70mW/m2), re spec tively (Fig. 10A). In most of the FSH, thecal cu lated Car bon if er ous heat-flow val ues were above 85mW/m2 (Fig. 10A). The Cre ta ceous heat flow gen er ally was above 60 mW/m2 and only in the Poznañ area val ues are inthe range of 40–50 mW/m2 (Fig. 10B).

Pomerania

The Car bon if er ous heat-flow val ues in crease in Pome-rania from NE (40 mW/m2) to SW (95 mW/m2) (Fig. 10A).The Cre ta ceous heat flow in creases from NE (30 mW/m2)to SW (70 mW/m2) in a more reg u lar man ner (Fig. 10B),and in the ma jor ity of Pomerania is in the range of 40–50mW/m2 (Fig. 10B).

Kujawy and Masovia

In Kujawy, the cal cu lated Car bon if er ous and Cretace-ous heat flows were in the range of 60–80 W/m2 (in creas ing slightly to the SW) and 40–50 mW/m2, re spec tively (Fig.10A, B). In Masovia (War saw De pres sion), the cal cu latedCar bon if er ous heat flow was in the range 40–50 W/m2,(Fig. 10A), while the Cre ta ceous heat flow var ied be tween30–45 mW/m2 (Fig. 10B).

THER MAL MA TU RITY

The vitrinite reflectance map (Fig. 11) was cal cu latedfor the top of the Car bon if er ous. It is in gen er ally goodagreement with pre vi ous mea sure ments of Rr (Bachleda-Curuœ and Semyrka, 1990; Bachleda-Curuœ et al., 1996;Burzewski et al., 1998; Grotek, 1998, 2005, 2006; Grotek et al., 1998; Matyasik et al., 1998; Wag ner, 1999; Botor et al.,2002b; Nowak, 2003, 2007; Górniak et al., 2004; Kotarba

et al., 2004, 2005; Resak et al., 2008; Botor et al., 2012). Inthe vi cin ity of the gas fields, the ma tu rity is in the range of0.7 to 2.0% Rr (Fig. 11).

Fore-Sudetic Homocline and Pomerania

In west ern and cen tral FSH, Rr val ues at the top of theCar bon if er ous are in the range of 0.7–2.0% (Fig. 11). How -ever, in the east ern FSH, ma tu rity lo cally reaches the high -est val ues of ~5.0% Rr (Fig. 11; see also Karnkowski, 1999; Wag ner, 1999; Nowak, 2003). In Pomerania, ma tu rity in -creases from the north and NE (be low 1.0% Rr) to wards thesouth and SW (up to 2–3% Rr) (Fig. 11). The high est val ues are in the Czaplinek–Pi³a area.

Kujawy and Masovia

The Rr val ues in Kujawy are usu ally very high (2–3%)reach ing a max i mum of 4–4.5% Rr in the area Kroœnie-wice–Kutno–Brzeœæ Kujawski (Fig. 11). In con trast, vitri-nite reflectance val ues are gen er ally be low 1.5% in Ma-sovia (Fig. 11).

GAS GEN ER A TION

The fi nal re sults of gas-gen er a tion mod el ling wereshown as a kerogen trans for ma tion ra tio (% TR) (Figs12–14). TR val ues at the top of the Car bon if er ous were cal -cu lated for the most im por tant phases of ba sin evo lu tion: (1) the lat est Car bon if er ous (Variscan pe riod; Fig. 12), (2) lat -est Late Tri as sic (Cimerian phase; Fig. 13), and (3) lat estCre ta ceous (Lara mide in ver sion; Fig. 14).

Thermogenic gases are gen er ated from kerogen mainlyin the range of 1–3.0% Rr (Cornford, 1998), be cause ther -mal ma tu rity above 1% Rr is re garded as min i mum for thegen er a tion of sig nif i cant amount of gases (e.g. Cornford,1998). How ever, this pro cess starts even at lower Rr val ues(Hunt 1996). Gas gen er a tion re veals con sid er able vari a tionin the dif fer ent zones of the Car bon if er ous ba sin, where thekerogen trans for ma tion ra tio (TR) reached val ues in therange of 20 to 100% (Figs 12–14). The high est TR oc curs in the zones of max i mum ma tu rity of or ganic mat ter. Gas gen -er a tion took place in sev eral pulses: Late Car bon if er ous,Me so zoic (Mid dle–Late Tri as sic to Late Ju ras sic), and Cre -ta ceous.


In the east ern FSH, sig nif i cant gas gen er a tion commen- ced as early as in the Late Car bon if er ous and the kerogentrans for ma tion ra tio reached ap prox i mately 100% by theend of this pe riod (Fig. 12; Kalisz IG1 well – Dymek IG1well). A peak ther mal ma tu rity of up to 5.0% Rr was lo callyob tained, lead ing to dry gas gen er a tion and over cook ing.Con se quently, gas gen er a tion in the east ern FSH was com -pleted in Variscan times be fore the Zechstein cover andmost of the hy dro car bons were lost. How ever, in the cen tral, west ern and north ern parts of the FSH, where pe tro leum po -ten tial still ex isted af ter the Car bon if er ous, gen er a tion re -


sumed in Mid dle Tri as sic–Late Ju ras sic and Late Cre ta -ceous times (Figs 13, 14), with the high est in ten sity in theLate Tri as sic to the Early Ju ras sic. In the NW of the FSH(Siciny IG-1, Paproæ, Objezierze IG1, Strzelce KrajeñskieIG1 wells), the kerogen TR reached over 80% (Figs 12–14).

Pomerania

The low est TR is in the NE part (east ern Pomerania andMasovia) of the Car bon if er ous ba sin, with val ues of be low40% (Figs 12–14). In Pomerania, a first-gen er a tion phasetook place, prob a bly in the Late Car bon if er ous (Fig. 12).How ever, the ma tu rity was too low at that time to have asig nif i cant ef fect on gas gen er a tion. In most places, the pe -tro leum po ten tial was not ex hausted dur ing this early gen er -a tion phase, which was fol lowed by two more gen er a tivephases in the Tri as sic–Ju ras sic and the Late Cre ta ceous,when ma tu rity reached more than 1.0% Ro (Figs 12–14).

Kujawy and Masovia

In the zones, where the hy dro car bon po ten tial was notex hausted in the Car bon if er ous (most ar eas of the Car bon if -er ous ba sin), two ma jor ep i sodes of hy dro car bon gen er a tion oc curred in the Tri as sic and/or Ju ras sic (Fig. 13) and theLate Cre ta ceous (Fig. 14). The range of kerogen trans for -ma tion was very vari able in these Me so zoic phases (from 20 to more than 90%). Dur ing the Mezozoic, gas gen er a tion inthe ax ial part of MPT be gan in the Early Tri as sic (Kroœnie-wice De pres sion, Kutno–£ódŸ area) and grad u ally in -creased un til the lat est Ju ras sic. In the re main ing parts of the MPT, gas gen er a tion be gan in the Late Tri as sic, reach ing amax i mum in the Early Ju ras sic, as in the west ern FSH. Bythe end of the Tri as sic, the TR reached 70% in the cen tralparts of the ba sin (Fig. 13). In the Konin–Kalisz area, gasgen er a tion con tin ued un til the Late Cre ta ceous. By the endof Cre ta ceous, gas gen er a tion was for the most part com -

370 D. BOTOR ET AL.

Fig. 11. Cal cu lated pres ent-day vitrinite reflectance at top of Car bon if er ous

pleted, es pe cially in the most deeply bur ied parts of the Car -bon if er ous ba sin. In al most the en tire area of Masovia, theTR val ues were low (be low 40%) at the end of the Car bon if -er ous (Fig. 12). By the end of the Cre ta ceous, the west ernpart of Masovia reached 70% TR, while the TR still re -mained very low in the east ern part (Figs 12–14).

GAS MI GRA TION MOD EL LING

Ba sic as sump tions

Mi gra tion mod el ling of gases was per formed, us ingflowpath anal y sis (Hantschel and Kauerauf, 2009). A mi -gra tion flowpath con nects the source-rock area, where theCar bon if er ous rocks are in the di rect con tact with clasticrocks of the Up per Rotliegend, and the top of the Up perRotliegend res er voir rocks, sealed by Zechstein evaporitesand playa sed i ments in the cen tral part of the ba sin (Fig. 15). Ce men ta tion pro cesses of the Up per Rotliegend res er voirrocks were dis re garded in the sim u la tion of gas mi gra tion,since it was as sumed that the po ros ity and per me abil ity evo -lu tion of the res er voir rocks through time was caused onlyby me chan i cal com pac tion.

Re sults of the gas mi gra tion mod el ling

The mi gra tion mod el ling re sults showed that gas mi gra -tion in the deeper part of the Rotliegend ba sin is well re con -structed out side the lim its of the vol ca nic cover (Fig. 15). Inthe case of gas ac cu mu la tions close of the Wolsztyn-Pogo-rzela High (area D in Fig. 16), the re con structed fill ing oftraps is only due to long-dis tance mi gra tion. In mi gra tionmod el ling on a re gional scale, gas mi gra tion along faultstransecting the Autunian and Car bon if er ous strata was nottaken into ac count. How ever, this mech a nism may havebeen pre dom i nant in the Zielona Góra De pres sion, as wellas in the area di rectly north of the Wolsztyn-Pogorzela High (Figs 15, 16).

The mod el ling re sults have shown that gas mi gra tioncon tin ued dur ing the sub si dence of the Pol ish Ba sin in theMe so zoic, mainly in the Late Tri as sic – Early Ju ras sic andLate Ju ras sic (Fig. 15), and was ter mi nated by the Late Cre -ta ceous in ver sion. In the cen tral part of the MPT, mi gra tioncom menced at the end of the Early Tri as sic in the Kroœnie-wice De pres sion. Gas mi grat ing to the NE dur ing that timecould have ac cu mu lated in the Szubin–Byczyna–Kutno an -ti cli nal struc ture (area A in Fig. 16) that was formed dur ingthe Tri as sic. At the same time, a con cen trated stream of gasmi grated from a lo cal gen er a tion cen tre north of Wrzeœniato wards the Fore-Sudetic Homocline (area C in Fig. 16).Dur ing the Late Tri as sic, the first gas ac cu mu la tions wereformed in the Poznañ Trough as a re sult of long-dis tancegas mi gra tion from the gen er a tion cen tre along the Pi³a–Szubin–Objezierze line and short-dis tance gas mi gra tionfrom the sub-Perm ian base ment of the Poznañ Trough (Fig.15). In the Mogilno–£ódŸ De pres sion, gas mi gra tion con -tin ued in the Ju ras sic, grad u ally de clin ing through the Cre -ta ceous. Con se quently, the fill ing of traps in the Rotliegendwas pos si ble dur ing the Ju ras sic–Cre ta ceous, even if thosetraps were formed rel a tively late (Fig. 15).

Mod el ling has shown that the great est mass of gas un -der went scat ter ing in the mar ginal parts of the Pol ish Ba sinalong the Teisseyre–Tornquist Zone from the end of the late Tri as sic to the end of the Early Ju ras sic and along the north -ern mar gin of Holy Cross Moun tains from the Mid dle Ju ras -sic to the end of the Late Ju ras sic. To a lesser ex tent, gas un -der went scat ter ing at the edge of the Wolsztyn-PogorzelaHigh. Be cause of the ces sa tion of gas mi gra tion in the cen -tral part of the MPT al ready at the end of the Mid dle Ju ras -sic and the sub se quent Al pine in ver sion of the ba sin, largeamounts of ni tro gen in the gas com po si tion can be ex pectedin the deeply burried po ten tial traps, lo cated along the lineSzubin–Byczyna–Kutno (Fig. 15, and area A in Fig. 16).The Pi³a–Konin zone could have sup plied the Mê¿yk–Obje- zierze–Wrzeœnia po ten tial ac cu mu la tion zone (Fig. 15 andarea C in Fig. 16). In the pro spec tive zones dis cussed, theRotliegend shows res er voir po ten tial in the depth in ter valdeeper than 3500–5500 m (Fig. 16).

DIS CUS SION

Burial and ther mal his tory

The sub si dence anal y sis re sults re viewed in this pa perdoc u ment an ini tial Early Perm ian syn-rift phase in the evo -lu tion of the Pol ish Ba sin that led to the de vel op ment of theMPT and was fol lowed by sig nif i cant ther mal sag ging inthe Late Perm ian – Early Tri as sic (255–241 Ma). Re peatedpe ri ods of ac cel er ated sub si dence also were noted for theLate Ju ras sic (157–152 Ma) and Cenomanian (~ 97–100Ma) (Dadlez et al., 1994; Stephenson et al., 2003; Resak etal., 2008). The de vel op ment of the Pol ish Ba sin was ter mi -nated by the Late Cre ta ceous and/or Early Paleogene in ver -sion that af fected the en tire Cen tral Eu ro pean ba sin sys tem(e.g., Mazur et al., 2005; Gast et al., 2010). In the ax ial partof the Mid-Pol ish Swell (in verted MPT), sed i ments inplaces were re moved down to the Lower Ju ras sic or eventhe Up per Tri as sic, whereas elon gated troughs at the flanksof the swell were filled with thick Up per Cre ta ceous syn-in -ver sion de pos its (e.g., Mazur et al., 2005).

Karnkowski (1999) pro posed a ther mal model as sum -ing con stant heat flow in the MPT and a Perm ian–Ju ras sicther mal anom aly in the FSH area char ac ter ised by rel a tively high heat flow. The heat-flow evo lu tion model pro posed inthis study is gen er ally sim i lar to that pro posed by Karn-kowski (1999) with some mod i fi ca tions ap plied. Firstly, aheat flow slightly lower than that of the pres ent day was as -sumed for the Cre ta ceous in the ax ial part of the MPT, onthe ba sis of the find ings of Poprawa and Andriessien(2006). Sec ondly, an ad di tional in crease of heat flow wasnec es sary in the east ern part of the MPT in the Tri as sic–Ju -ras sic, as doc u mented by K-Ar dat ing and diagenetic stud ies(Koz³owska and Poprawa, 2004). The cal cu lated heat flowval ues in the Palaeozoic ranges from 80 to 140 mW/m2, de -creas ing in the Me so zoic and Caino zo ic (Fig. 10A, B). Forthe Perm ian–Ju ras sic the heat-flow model pos tu lated here co -in cides with that of Karnkowski (1999) in the MPT only. Inthe SE part of Pol ish Ba sin, the higher heat-flow val ues werepre dicted for the Perm ian–Ju ras sic.



Ex tremely high val ues of heat flow and burial in the SEpart of the FSH can be at trib uted to the advective heat trans -port that was sug gested by ma tu rity mod el ling (Maækowski, 2005; Poprawa et al., 2005) and by 2-D fluid-flow mod el -ling (Maækowski et al., 2008). In the FSH, cal i bra tion isusu ally very good for the Car bon if er ous sec tion of pro files,but much worse for the Perm ian and Me so zoic over bur den(Botor, 2011b, 2012b; Botor et al., 2012). Gen er ally, in theeast ern FSH (Marcinki IG-1 well – Wiêcki IG-1 well), ther -mal ma tu rity of the Car bon if er ous or ganic mat ter was rea-ched be fore the Perm ian, as clearly ev i denced by breaks inthe Rr pro files in wells (Fig. 8; Maækowski, 2005; Poprawaet al., 2005; Maækowski et al., 2008; Botor, 2011b, 2012b;Botor et al., 2012) and the dis tri bu tion of Rr at the top of the Car bon if er ous (Fig. 11). In con trast, ther mal ma tu rity wasachieved in the early Me so zoic in the cen tral and west ernFSH (e.g., Siciny IG-1 well area, Fig. 8; Maækowski et al.,

2008; Botor, 2011b, 2012b, Botor et al., 2012), but an op -pos ing view was preseted by Poprawa et al., (2005) on theVariscan or i gin of or ganic ma tu rity in that area. The burialhis tory of the east ern FSH was also char ac ter ised by EarlyCre ta ceous up lift and ero sion. In the east ern FSH, the es ti -mates for Car bon if er ous–Early Perm ian heat flow and Car -bon if er ous over bur den ero sion were in the range of 87–140mW/m2 (Fig. 10A) and 2000 to 4000 m (Fig. 9A), re spec -tively. In con trast, in the west ern FSH (e.g., Paproæ–SicinyIG-1 wells area; Fig. 8E) rel a tively mi nor Variscan ero sionwas pre dicted (300–2000 m, Fig. 9A), whereas the heatflow value (80–110 mW/m2; Fig. 10A) was typ i cal for theMid-Eu ro pean Variscides (Franke et al., 2000). Sen si tiv ityanal y sis of the mod els for the FSH area showed that they are con sis tent and al low for best-fit cal i bra tion (Botor, 2011b,2012b; Botor et al., 2012). Rr pro files (e.g., Siciny IG-1well) did not re veal any char ac ter is tic breaks across the Car -bon if er ous/Perm ian un con formity, as in the east ern FSH(east of the Marcinki IG1– Kalisz IG-1 line). There fore, the

372 D. BOTOR ET AL.

Fig. 12. De gree of kerogen trans for ma tion (TR%) in Car bon if er ous source rocks (re ferred to top of Car bon if er ous) cal cu lated for end ofCar bon if er ous

con clu sion can be drawn that ther mal ma tu rity of Car bon if -er ous rocks in the cen tral and west ern FSH was reached inthe Me so zoic as ev i denced also by the wide oc cur rence ofgas fields in the Rotliegend. These fields were charged from Car bon if er ous source rocks. If the gas gen er a tion was de -vel oped and com pleted in the Late Car bon if er ous be fore the Zechstein seal ing, all gas would have been lost, ow ing toerosion from the lat est Car bon if er ous to the Early Perm ian.

In the east ern FSH, the main pos si ble rea son for highheat flow was prob a bly vol ca nic and as so ci ated hy dro ther -mal ac tiv ity in that area (Karnkowski, 1999; Poprawa et al.,2005; Maækowski et al., 2008). A very char ac ter is tic fea ture is the great thick ness (2–4 km) of the eroded sec tion, re con -structed from ma tu rity mod el ling. This could have been re -lated to the Late Car bon if er ous tec tonic burial and re sul tantther mal dom ing, com bined with a post-collisional iso staticre ac tion (Poprawa et al., 2005). How ever, the ex tremelydeep burial in the sec tions pen e trated by some wells (above4 km) re con structed from ma tu rity mod el ling, also can bein ter preted as an arte fact caused by con vec tive heat trans -port, solely due to hy dro ther mal ac tiv ity (Poprawa et al.,2005; Maækowski et al., 2008). The cur rent data do notsolve this co nun drum.

The Late Perm ian–Me so zoic and Caino zo ic burial andthe mod er ate heat flow (~50–60 mW/m2) did not changethe ma tu rity pro file of the Car bon if er ous sed i ments (Spe-czik and Koz³owski, 1987; Maækowski, 2005; Poprawa etal., 2005). The cal cu lated thick ness of the eroded over bur -den (Fig. 9) can be de cep tive, be cause it is greater than theamount of ero sion, de rived from trend anal y sis and palaeo-thicknesss of the Car bon if er ous strata (Papernik and Rei-cher, 1998). Ad di tion ally, if advective heat trans port is as -sumed in the east ern FSH, the mod els can be cal i brated, us -ing the thick ness of eroded over bur den be low 1000 m(Maækowski et al., 2008). How ever, Francu et al. (2002)pos tu lated 4–8 km of Late Car bon if er ous over bur den, withonly mod er ately el e vated heat flow (70 mW/m2) for theDrahany Up land, in the Moravo-Sielsian Culm ba sin (thearea south of the east ern FSH). The cal cu lated thick ness oferoded sed i ments ranges from 4–9 km for the Moravo-Sile-sian thrust-and-fold belt to 1.6 km far ther east, in the mar -ginal Variscan fore land ba sin. Francu et al. (2002) as sumedthat deep burial was achieved by de po si tion of a thick flysch suc ces sion, pos si bly fol lowed by the em place ment of theVariscan orogenic wedge from the NW dur ing the Viséanand Late Car bon if er ous. The ac cre tion mech a nism withcompression and short en ing would first in crease the burialand later cause de tach ment, imbrication, and ex hu ma tion ofthe pre vi ously bur ied strata within the ad vanc ing orogenicwedge. The con fi dence in the es ti mates by Francu et al.(2002) is lim ited, since the re con struc tion of the burial his -tory and palaeogeothermal con di tions is much more com -plex, when thrust ing is in volved and the sed i men tary rocksare imbricated and stacked. Fast underthrusting of a coldcrustal sur face be low an over rid ing nappe sheet causes low -er ing of the geo ther mal gra di ent in fron tal orogenic belts.As a re sult, tec tonic burial of ten is as so ci ated with a loweror equal, but not higher thermal overprint than that of asolely sedimentary cover of the same thickness (Angevineand Turcotte, 1983; Cermak and Bodri, 1996).

The re gional meta mor phic and diagenetic pat tern andthe pres ent ba sin mod el ling sug gest that the diagenetic andvery low-grade meta mor phic grade could not have been at -tained merely by high geo ther mal gra di ents, with out sig nif i -cant burial in the Variscan orogen. Sim i lar re la tion ships be -tween the burial and ther mal his to ries and the ge om e try ofthe Variscan belt and its fore land ba sin are ob served in theRuhr Ba sin, Rhenish Mas sif, and ex ter nal Variscides ofsouth west Eng land (Warr et al., 1991; Littke et al., 1994).How ever, Gayer et al. (1998) con cluded that the ther malpat tern sug gests the de vel op ment of coal ma tu rity as a con -se quence of the Variscan hy dro ther mal flow in SouthWales. In or der to solve this prob lem de fin i tively, it wouldbe nec es sary to per form stud ies of com pac tion trends, aswas done for Pomerania (Stefaniuk et al., 1996). What everthe rea son for the el e vated tem per a ture in the FSH, or ganicmat ter achieved high ma tu rity in the lat est Car bon if er ous,whereas the Permian to Mesozoic organic matter showsonly mild maturity.

Pomerania

In Pomerania, the re con struc tion of a com pre hen siveand unique ther mal his tory is dif fi cult, ow ing to the in ad e -quate num ber of ther mal ma tu rity measurments (e.g., Rr) insome parts of pro files and prob lems with the op ti mal cal i -bra tion, us ing dif fer ent heat-flow sce nar ios in the wellsstud ied (Burzewski et al., 1996, 1998; Kotarba et al., 2004;Resak et al., 2008).

Kujawy–Masovia area

The best-fit model cal i bra tion in the cen tral part of theMPT was achieved us ing heat-flow val ues, lower than those pres ently ob served (Botor, 2011a). This is sup ported by in -de pend ent in for ma tion on the lower geo ther mal palaeogra-dient, based on ap a tite fis sion-track dat ing (Poprawa andAndriessen, 2006). How ever, a very sim i lar qual ity of mo-del cal i bra tion can be also ob tained (Botor, 2011a), as sum -ing con stant heat flow in the Me so zoic, as suggested byKarnkowski (1999).

On the flanks of the MPT, the ma tu rity field was de ter -mined with ref er ence to the Ju ras sic to Cre ta ceous burial,prob a bly as so ci ated with an extensional tec tonic re gime(Kutek, 1994; Hakenberg and Œwidrowska, 1997; Poprawa, 1997). Ad di tion ally, an in crease in heat flow was as sumedin the Masovia area (Korabiewice PIG1 – Mszczonów IG1wells) in the Ju ras sic for con sis tency with the K-Ar ages ofdiagenetic illite in sand stones that ac cord ing to Koz³owskaand Poprawa (2004) imply a heat-flow anomaly.

GAS GEN ER A TION

The re sults of mod el ling in di cate that the Car bon if er ous sed i ments at tained their ther mal ma tu rity be tween the LateCar bon if er ous and the Cre ta ceous. Sev eral stages of ther-mogenic gas gen er a tion and ex pul sion could be dis tin -guished (Karnkowski, 1996, 1999, 2007; Burzewski et al.,1998; Kotarba et al., 2004, 2005; Botor 2011a, b). How -


ever, in con trast to pre vi ous pub lished stud ies, the pres entac count con sid ers the en tire Car bon if er ous sub stra tum ofthe Rotliegend ba sin (Figs 12–14). The Lower Car bon if er -ous source rocks gen er ated gas in two phases: in the LateCar bon if er ous and later from the Early Tri as sic to the LateCre ta ceous. In con trast the Up per Car bon if er ous sourcerocks gen er ated gas only in the Me so zoic, ow ing to in suf fi -cient burial in the Variscan stage of de vel op ment (Botor,2011b, 2012b). As sug gested for some parts of the Ger manBa sin (Pletsch et al., 2010), Westphalian gases re placed and dis placed older gases that had come from Lower Car bon if -er ous source rocks. This caused the mix ing of gases in thecon ven tional gas fields (Pletsch et al., 2010).

Tak ing into ac count the geo log i cal de vel op ment of thestudy area, sev eral dif fer ent ther mal mod els can be ap pliedsuc cess fully to achieve very good cal i bra tion re sults. How -ever, the tim ing and amount of hy dro car bons gen er ated ac -cord ing to var i ous mod els are not much dif fer ent, at least in

the cen tral part of the MPT (Botor, 2011a). In ad di tion, be -cause of salt tec ton ics, or ganic mat u ra tion and gas gen er a -tion can be sig nif i cantly de layed in some Car bon if er oussource rocks be low salt diapirs and pil lows, as was the casein the Ger man Ba sin (Schwarzer and Littke, 2007). In gen -eral, it can be con cluded that the ther mal ma tu rity of theCar bon if er ous rocks, ex cept for in the east ern FSH, wasreached in the Me so zoic, which also is sup ported by thewide oc cur rence of gas fields in the Rotliegend. As statedabove, gas that had ac cu mu lated in these fields and orig i -nated from the Car bon if er ous source rocks would have been lost dur ing ero sion near the Car bon if er ous–Perm ian bound -ary, if gas generation had been developed and completedbefore the Zechstein sealing.

The de gree of trans for ma tion of Car bon if er ous kero-gens cor re sponds with the ini tial and main phases of liq uidhy dro car bon gen er a tion in Masovia and north ern Pome-rania. In the ax ial part of the MPT and in the FSH, Car bon if -

374 D. BOTOR ET AL.

Fig. 13. De gree of kerogen trans for ma tion (TR%) in Car bon if er ous source rocks (re ferred to top of Car bon if er ous) cal cu lated for theend of Tri as sic

er ous kerogens are char ac ter ized by a de gree of trans for ma -tion that cor re sponds to the phase of gas con den sate gen er a -tion, but above all, the phase of thermogenic generation ofdry gas.

GAS MI GRA TION

The great est amounts of gases were gen er ated and ex -pelled from the Car bon if er ous source rocks in the sub stra -tum of the Mogilno-£ódŸ De pres sion, the ax ial part of theMPT, and the Lower Silesian (Zielona Góra) De pres sion(Figs 12–15) (see also Maækowski et al., 2008; Górecki etal., 2011). Tak ing into ac count the K-Ar age dat ing ofauthigenic illites, which can be used as a proxy for the clo -sure of gas mi gra tion paths, this should have hap pened inthe Me so zoic, mostly from the Early Ju ras sic to the EarlyCre ta ceous (Lee et al., 1985; Ham il ton et al., 1989; Liewig

and Clauer, 2001; Michalik, 2002; Protas et al., 2006; Mali- szewska et al., 2009, and ref er ences therein). There fore, itseems rea son able that nu mer ous res er voirs in the Rotlie-gend ba sin were filled by hy dro car bons be fore the end ofthe Late Ju ras sic. This also is strongly sup ported by gas-mi -gra tion mod el ling (Fig. 15; Maækowski et al., 2008), whichshowed that mi gra tion had an ep i sodic char ac ter and lastedfrom the Late Triassic to the Early/Late Jurassic.

The very high kerogen trans for ma tion prob a bly causedni tro gen gen er a tion, par tic u larly in the deep est part of theba sin (e.g., the Kujawy–Kutno area) from the Tri as sic to the Early Ju ras sic. Nat u ral gas, re cov ered in the North Ger manBa sin, ad ja cent to the Pom er a nian seg ment of the Pol ish Ba -sin, is dom i nated by ni tro gen (over 90% – Gerling et al.,1997). Such an ex tremely high ni tro gen con tent must havebeen re lated to the fact that ni tro gen is gen er ated from or -ganic mat ter within a sed i men tary ba sin at higher tem per a -tures than meth ane. Ni tro gen-rich gases are mainly formed


Fig. 14. De gree of kerogen trans for ma tion (TR%) in Car bon if er ous source rocks (re ferred to top of Car bon if er ous) cal cu lated for theend of Cre ta ceous

dur ing the fi nal stage of gas gen er a tion, when sed i men taryrocks are trans formed into meta mor phic rocks (e.g., Littkeet al., 1995).

The dis tri bu tion and con tent of ni tro gen and he liumwithin nat u ral gas, found in the Pol ish Rotliegend ba sin(Karnkowski, 1993, 1999; Lokhorst, 1997), dem on stratethe rel a tively high ni tro gen con tent (45–80%) in Pomeraniaand the erra- tic oc cur rences of he lium, found in only a fewwells. It seems that the pres ence of he lium is con nected with deep faults or frac ture zones, along which it could have mi -grated up ward (Karnkowski, 1999). The vari abil ity of thenitrogen con tent in the nat u ral gas de creases from the Ger -man Ba sin to wards the East Eu ro pean Plat form (Lokhorst,1997). Since the gen er a tion of ni tro gen, due to the high-tem per a ture trans for ma tion of or ganic mat ter, is widely ac -cepted in Ger many, a sim i lar ex pla na tion might be con sid -ered for the Pomerania re gion. This might be the case, evenif the tem per a tures ex pe ri enced by the Car bon if er ous source rocks were lower in NW Po land than in the Ger man Ba sin

and they de creased from west to the east. Al though gas gen -er a tion in Pomerania was ini ti ated in the Late Car bon if er ous the sec ond and main phase of this pro cess oc curred in theMe so zoic. The Car bon if er ous source rocks, which weresub jected to a lower ther mal re gime, could ma ture slowlyand re lease both ni tro gen and meth ane.

The dif fer ent dis tri bu tion pat terns of he lium and ni tro -gen con tent are vis i ble in the south ern part of the Pol ish Ba -sin: ni tro gen con tent in creases to wards the ba sin mar gins,but he lium is con cen trated in one dis tinct area (NE part ofthe FSH). This is the case, not only for sin gle wells, but alsofor en tire gas plays (Kotarba et al., 1992; Karnkowski,1999). The north east ern FSH is one of the few places in theworld, where con densed gas pro vides in dus trial amounts ofhe lium, both due to the high con tent in nat u ral gas plays and the sig nif i cantly large vol ume. The ni tro gen con tent is alsohigh, from 40 to 75% (Pletsch et al., 2010). The meth anecon tent in creases to wards the ba sin cen tre and the char ac -ter is tic lo ca tions of higher meth ane amounts within a ni tro -

376 D. BOTOR ET AL.

Fig. 15. Gas mi gra tion paths at top of Up per Rotliegend res er voir rocks (mod i fied af ter Maækowski et al., 2008)

gen-he lium field in di cate mi gra tion of it from the ba sin cen -tre to wards the south. The area with a high he lium con cen -tra tion cor re sponds to the part of the Pol ish Ba sin, af fectedby the high est heat flow dur ing the Perm ian through the Me -so zoic.

CON CLU SIONS

The most im por tant re sults of the ma tu rity mod el lingare sum ma rised below:

1. The hy dro car bon po ten tial of the Pol ish RotliegendBa sin sig nif i cantly ex ceeds the re serves of gas fields disco-vered to date.

2. Car bon if er ous or ganic mat ter con sti tuted the mainsource of the hy dro car bons, ac cu mu lated in the Rotliegendres er voirs. The re sults of the geo chem i cal and petrographicre search, car ried out so far on the or ganic mat ter from theCar bon if er ous strata in Po land, have shown that the disper-

sed or ganic mat ter is mostly of a humic na ture (gas-prone,Type III kerogen). Subordinately, only in the Tournaisianand Viséan de pos its, kerogen of al gal-ma rine or i gin (oil-prone, Type II kerogen) and mixed Type II/III kerogen oc -cur. How ever, these have a low hy dro gen con tent, whichac cen tu ates their rather gas-prone char ac ter. The pre dom i -nat ing humic kerogen de ter mined the char ac ter of the Car -bon if er ous or ganic mat ter as a source of gas eous hy dro car -bons. The quan tity of dis persed or ganic mat ter is vari able,some times quite large with averages oscillating aroundvalues in the order of 1–2% TOC.

3. In the Car bon if er ous sec tion, a pro gres sive in creasein ma tu rity of or ganic mat ter with burial depth can be ob -served from ap prox i mately 0.5% Rr at the top of the West-phalian (mar gins of the MPT) to over 5.0% Rr in the bot tom parts of the Lower Car bon if er ous (east ern FSH). The ma jor -ity of hy dro car bon fields oc cur in the zones, where the topof the pre-Perm ian base ment at tained a ther mal ma tu rity inthe or der of 1.0–2.0% in the vitrinite reflectance scale. The


Fig. 16. Lo ca tion map of pro spec tive zones at top of Rotliegend (mod i fied af ter Burzewski et al., 2009; Górecki et al., 2011)

pres ence of ef fec tive source rocks is re stricted to the zoneswith maturity exceeding 1.0% Rr.

4. The thermogenic gen er a tion of hy dro car bons fromthe Car bon if er ous sources took place from the late West-phalian and through out the Me so zoic, up to the Late Cre ta -ceous. Its tim ing and ad vance ment re veal con sid er able vari -abil ity across the Car bon if er ous ba sin, reach ing a kerogentrans for ma tion of ap prox i mately up to 100% in the zones ofmax i mum ma tu rity of or ganic mat ter. In the east ern FSH,gas gen er a tion was com pleted in Variscan time be fore thecov er ing of it by the Zechstein and most gases were dis -persed in the at mo sphere. In other parts of the FSH, gas gen -er a tion con tin ued in the Me so zoic, with the high est rate inthe Late Tri as sic to Early Ju ras sic. In the ax ial part of theMPT, gas gen er a tion com menced in the Early Tri as sic (theKutno–£ódŸ area) and grad u ally in creased up to the lat estJu ras sic, which was gen er ally re lated to high burial and con -duc tive heat flow. How ever, in the re main ing parts of theMPT, gas gen er a tion be gan in the Late Tri as sic and reacheda max i mum in the Early Ju ras sic, also in the FSH. In theKonin–Kalisz area, gas generation continued until the LateCretaceous.

5. Hy dro car bon mi gra tion pro ceeded in pulses of vari -able in ten sity. The main phases of gas mi gra tion took placein the Late Tri as sic, Early Ju ras sic, and Late Ju ras sic. Mi -gra tion ceased in the Cre ta ceous. In the light of the re sultsof hy dro car bon mi gra tion mod el ling, the most pro spec tivear eas for ex plo ra tion are rep re sented by the Konin–Mala-nów and Szubin–Byczyna–Kutno zones, and the Mê¿yk–Objezierze–Wrzeœnia zone. The area near the NE mar gin ofthe Wolsztyn-Pogorzela High re mains pro spec tive. The mo- delling has shown that the great est amount of gas was dis -persed in the mar ginal parts of the ba sin: (a) along the Teis-seyre–Tornquist Zone, be tween the Late Tri as sic and theend of Early Ju ras sic, and (b) at the north ern mar gin of theHoly Cross Mts., from the Mid dle to Late Ju ras sic. In themar ginal zone of the Wolsztyn-Pogorzela High, the gasexperienced less dispersion.

Ac knowl edge ments

The Fac ulty of Ge ol ogy, Geo phys ics and En vi ron mental Pro -tec tion, AGH Uni ver sity of Sci ence and Tech nol ogy, is deeply in -debted to Schlumberger for the soft ware, which was pro vided inthe frame work of the Uni ver sity Grant Pro gram. This study wascar ried out within the frame work of a pro ject, com mis sioned bythe Min is try of the En vi ron ment (No 562/2005/Wn-06/FG-sm-tx/D) and fi nanced from NFEP and WM, AGH UST stat u tory re -search no 11.11.140.883 and par tially 11.11.140.562 and re searchpro gram MNiSW WND-POIG.01.01.02.00.122/09 (AGH – 72.72. 140.8425) “Im prove ment of the ef fec tive ness of seis mic sur veyfor pros pect ing and ex plo ra tion for nat u ral gas de pos its in Rotlie-gend for ma tions”, su per vised by Wojciech Górecki. We alsowould like to ex press our grat i tude to the re view ers (Pawe³ Po-prawa and Anon y mous Re viewer) and ed i tor (Stanis³aw Mazur)for their ex tremely valu able in put, which im proved the qual ity ofthe pa per.

REF ER ENCESAngevine, C. L. & Turcotte, D. L., 1983. Pe tro leum gen er a tion in

overthrust belts. AAPG Bul le tin, 67: 235–241.

Bachleda-Curuœ, T. & Semyrka, R., 1990. Bilans wêglowodorowymezozoicznego kompleksu osadowego na Ni¿u Polskim. Wy-dawnictwa AGH, Kraków, 216 pp. [In Pol ish].

Bachleda-Curuœ, T., Burzewski, W., Halat, Z. & Semyrka, R.,1996. Hy dro car bon gen er a tion po ten tial of sed i men tary for -ma tions in the West ern Pomerania. Oil and Gas News, 6:163–170.

Bahranowski, K., Protas, A., Gawe³, A. Górniak, K. Ratajczak, T.& Szyd³ak, T., 2007. Black shales of the Lower Car bon if er -ous: source rocks of bi tu men ac cu mu la tions in the West ernPomerania area. Przegl¹d Geologiczny, 55: 281–282. [In Pol -ish, Eng lish ab stract].

Benek, R., Kramer, W., McCann, T., Scheck, M., Negendank, F. J. W., Korich, D., Huebsher, H.-D. & Bayer, U., 1996. Permo-Car bon if er ous magmatism of the North east Ger man Ba sin.Tectonophysics, 266: 379–404.

Botor, D., 2011a. Gas gen er a tion 1-D mod el ling in the Car bon if er -ous sed i ments in the deep part of the Pol ish Rotliegend ba sin.Kwartalnik AGH Geologia, 37: 503–516.

Botor, D. 2011b. The charge his tory of the Rotliegend gasfields inthe west ern Po land. 73 EAGE Con fer ence & Ex hi bi tion In -cor po rat ing SPE EUROPEC 2011: 23–26 May 2011, Vi enna, Ex tended Ab stracts: 102–107.

Botor, D., 2012a. The Car bon if er ous–Rotliegend pe tro leum sys -tem in the Ger man–Dutch part of the ba sin – im pli ca tions forgas ex plo ra tion in the Pol ish part of the Rotliegend ba sin.Biuletyn Pañstwowego Instytutu Geologicznego, 448: 159–168.

Botor, D., 2012b. Two-stages gas gen er a tion in the Car bon if er ousshales of the south ern part of the Fore-Sudetic Monocline(SW Po land). Book of Ab stracts, Geoshale Con fer ence, War -saw, 14–16.05.2012. Pol ish Geo log i cal In sti tute – Na tionalRe search In sti tute, War saw, p. 115.

Botor, D. & Kosakowski, P., 2000. Ap pli ca tion of the nu mer i calmod el ling in the re con struc tion of ther mal his tory and pe tro -leum gen er a tion: an over view of the meth ods. Przegl¹d Geo-logiczny, 49: 239–252. [In Pol ish, Eng lish ab stract].

Botor, D. & Littke, R., 2003. 2-D nu mer i cal mod el ling by PE-TROMOD soft ware of the burial and ther mal his tory of thecoal-bear ing Lublin Car bon if er ous Ba sin. Pro ceed ings of theIn ter na tional. Con fer ence: Ge ol ogy of Coal-Bear ing Bas ins,Kraków, 20-21.04.2004. Wydawnictwo Akademii Górniczo-Hutniczej, Kraków, pp. 42–46.

Botor, D., Kuœmierek, J., Maækowski, T. & Kosakowski, P.,2002a. Nu mer i cal mod el ling of ex pul sion and mi gra tion ofthe hy dro car bons: case stud ies from Pol ish sed i men tary bas -ins. Przegl¹d Geologiczny, 51: 117–130 [In Pol ish, Eng lishab stract].

Botor, D., Kotarba, M. & Kosakowski, P., 2002b. Pe tro leum gen -er a tion in the Car bon if er ous strata of the Lublin trough (Po -land); an in te grated geo chem i cal and nu mer i cal mod el lingap proach. Or ganic Geo chem is try, 33: 461–476.

Botor, D., Papiernik, B., Maækowski, T., Reicher, B., Machowski,G. & Górecki, W., 2012. The ther mal his tory of the Car bon if -er ous source rocks in the Fore-Sudetic Monocline, Po land.Ex tended Ab stracts, 74 EAGE Co pen ha gen, Den mark. 4–6.06.2012. Eu ro pean As so ci a tion of Geoscientists & En gi neers, Co pen ha gen, pp. 211–216.

Breitkreuz, C., Ken nedy, A., Geiss ler, M., Ehling, B.-C., Kopp, J.,Muszyñski, A., Protas, A. & Stouge, S., 2007. Far East ernAvalonia: its chronostratigraphic struc ture re vealed bySHRIMP zir con ages from Up per Car bon if er ous to LowerPerm ian vol ca nic rocks (drill cores from Ger many, Po landand Den mark). Geo log i cal So ci ety of Amer ica Spe cial Pub li -ca tions, 423: 173–190.

378 D. BOTOR ET AL.

Burzewski, W., 1984. Geotektoniczne kryteria powstawania wê-glowodorów paleozoicznym profilu obszaru przedsudec-kiego. Prace Geologiczne Komisji Nauk Geologicznych Pols- kiej Akademii Nauk, 126: 1–91. [In Pol ish].

Burzewski, W., 1997. Geologiczne uwarunkowania realiów naftowych Polski. In: Górecki, W. (ed.), Rozwój polskiej myœli wposzukiwaniach naftowych. Wydawnictwo Plat an, Kraków,pp. 134–164. [In Pol ish].

Burzewski, W., Kotarba, M., Botor, D., Kosakowski, P. & S³up-czyñski, K., 1998. Hy dro car bon gen er a tion and ex pul sionmod el ling of the Late Pa leo zoic de pos its in the Radom–Lub-lin and Pomerania ar eas of the Pol ish Low lands. In: Narkie-wicz, M. (ed.), Sed i men tary ba sin anal y sis of the Pol ish Low -lands. Prace Pañstwowego Instytutu Geologicznego, 165:273–284. [In Pol ish, Eng lish ab stract].

Burzewski, W., Maækowski, T., £apiñkiewicz, P., Bachleda-Cu-ruœ, T. & Semyrka, R., 1996. Mod el ling of the paleothermalgra di ent for deteremination of the dis tri bu tion of the hy dro car -bon phases in the West ern Pom er a nian De vo nian–Car bon if er -ous Com plex. Oil and Gas News from Po land, 6: 171– 174.

Burzewski, W., Górecki, W., Maækowski, T., Papiernik, B. &Reicher, B., 2009. Prog nos tic gas re serves – un dis cov ered po -ten tial of gas in the Pol ish Rotliegend Ba sin. Kwartalnik AGH Geologia, 35: 123–128. [In Pol ish, Eng lish ab stract].

Cermak, V. & Bodri, L., 1996. Time-de pend ent crustal tem per a -ture mod el ing – Cen tral Alps. Tectonophysics, 257: 7–24.

Cornford, C., 1998. Source rocks and hy dro car bons in the NorthSea. In: Glen nie, K. W. (ed.), Pe tro leum ge ol ogy of NorthSea. Ba sic Con cepts and Re cent Ad vances. Blackwell, Lon -don, pp. 137–173.

Dadlez, R., 2003. Me so zoic thick ness pat tern in the Mid-Pol ishTrough. Geo log i cal Quar terly, 47: 223–240.

Dadlez, R., 2006. The Pol ish Ba sin—re la tion ship be tween thecrys tal line, con sol i dated and sed i men tary crust. Geo log i calQuaterly, 50: 43–58.

Dadlez, R., Kowalczewski, Z. & Znosko, J., 1994. Some key prob -lems of the pre-Perm ian tec ton ics of Po land. Geo log i calQuarterly, 38: 169–189.

Dadlez, R., Narkiewicz, M., Stephenson, R. A., Visser, M. T. M.& Van Wees, J.-D., 1995. Tec tonic evo lu tion of the Mid-Pol -ish Trough: mod el ling im pli ca tions and sig nif i cance for cen -tral Eu ro pean ge ol ogy. Tectonophysics, 252: 179–195.

Dadlez, R., JóŸwiak, W. & M³ynarski, S., 1997. Sub si dence andin ver sion in the west ern part of the Pol ish Ba sin – data fromseis mic ve loc i ties. Geo log i cal Quar terly, 41: 197–208.

Dadlez, R., Marek, S., & Pokorski, J., 1998. Palaeogeographic At -las of Epicontinental Perm ian and Me so zoic in Po land (1:2500 000). Pol ish Geo log i cal In sti tute, Warszawa.

Doornenball, H. & Stevenson, A., 2010. Pe tro leum Geo log i cal At -las of the South ern Perm ian Ba sin Area, (UK to Po land).EAGE Pub li ca tions, Houten, The Neth er lands.

Espitalié, J., Deroo, G. & Mar quis, F., 1985. La pyrolyse Rock-Eval et ses ap pli ca tions. French Pe tro leum In sti tute Re vue,40: 755–784.

Francu, J., Kalvoda, J., Poelchau, H. S. & Otava, J., 2002. Burialand up lift his tory of the Palaeozoic Flysch in the Variscanfore land ba sin (Czech Re pub lic). Eu ro pean Geoscience Un -ion Stephan Mueller Spe cial Pub li ca tion Se ries, 1: 167–179.

Franke, W., Haak, V., Oncken, O. & Tan ner, D., 2000. Orogenicpro cesses: quan ti fi ca tion and mod el ling in the Variscan belt.Spe cial Pub li ca tions of the Geo log i cal So ci ety, Lon don, 179:1–345.

Gast, R. E., Dusar, M., Breitkreuz, C., Gaupp, R., Schnei der, J.W., Stemmerik, L., Geluk, M. C., Geiss ler, M., Kiersnowski,H., Glen nie, K. W., Kabel, S. & Jones, N. S., 2010. Rotlie-

gend. In: Doornenbal, J. C. & Stevenson, A. G. (eds), Pe tro -leum Geo log i cal At las of the South ern Perm ian Ba sin Area.EAGE Pub li ca tions, Houten, pp. 101–121.

Gayer, R. A., Garven, G. & Rickard, D. T., 1998. Fluid mi gra tionand coal-rank de vel op ment in fore land bas ins. Ge ol ogy, 26:679–682.

Gerling, P. Idiz, E., Everlien, G. & Sohns, E., 1997. New as pectson the or i gin of ni tro gen in nat u ral gas in north ern Ger many.Geologisches Jahrbuch, D-103: 65–84.

Górecka-Nowak, A., 2007. Palynological con straints on the age of the Car bon if er ous clastic suc ces sion of SW Po land (Fore-Sudetic area) based on miospore data. Geo log i cal Quar terly,51: 39–56.

Górecki, W., Weil, W. & Wolnowski, T., 1995. Oil and gas ac cu -mu la tion po ten tial of the West ern Pomerania (North-West ernPo land). Ab stracts of Con fer ence on Mod ern Ex plo ra tion andIm proved Oil and Gas Re cov ery Meth ods. AGH, Kraków, pp. 102–103.

Górecki, W., 2006. At las of geo ther mal re sources of Me so zoic for -ma tions in the Pol ish Low lands. Wydawnictwo AGH, Kra-ków, 484 pp.

Górecki, W., 2008. Prog nos tic Re sources and Un dis cov ered Nat u -ral Gas Po ten tial of Rotliegend and Zechstein Lime stone De -pos its in Po land. Un pub lished re port of the pro ject no. 562/2005/Wn-06/FG-sm-tx/D funded by Min is try of En vi ron ment of Po land in 2005–2008. De part ment of Fos sil Fu els, Fac ultyof Ge ol ogy, Geo phys ics and En vi ron men tal Pro tec tion, AGH UST, Kraków, 707 pp. [In Pol ish].

Górecki, W., Papiernik, B., Maækowski, Reicher, B., Botor, D.,Burzewski, W. & Machowski, G., 2011. Hy dro car bon po ten -tial of the Car bon if er ous – Lower Perm ian To tal Pe tro leumSys tem in the Pol ish part of the SPB. Ex tended ab stracts,73rd EAGE Con fer ence & Ex hi bi tion in cor po rat ing SPEEUROPEC, 23–26 May, Vi enna, P298. EarthDoc, EAGE Pu-blications B.V. http://www.earthdoc.org/pub li ca tion/pub li ca -tionde tails/?pub li ca tion=51128 [30.12.2013].

Górniak, K., Wag ner, M., Bahranowski, K., Gawe³, A., Ratajczak, T. & Szyd³ak, T., 2004. Ther mal his tory of Palaeozoic sourcerocks in West ern Pomerania (NW Po land): illite-smectite andvitrinite reflectance geothermometers. In: Németh, T. & Ter-bócs, A. (eds), 2nd Mid-Eu ro pean Clay Con fer ence, Miskolc,Hun gary, 20–24 Sep tem ber, 2004. Acta Universitatis Szege-diensis (Mineralogica-Petrographica Ab stract Se ries), 4: 46.

Gradstein, F. M., Ogg, J. G., Smith, A. G., 2004. A Geo logic TimeScale 2004. Cam bridge Uni ver sity Press, Cam bridge, pp. 3–589.

Grocholski, W., 1975. Variscides of south ern Wielkopolska. Prze- gl¹d Geologiczny, 23: 171–174. [In Pol ish, Eng lish ab stract].

Grotek, I., 2006. Ther mal ma tu rity of or ganic mat ter from the sed -i men tary cover de pos its from Pom er a nian part of the TESZ.In: Matyja, H. & Poprawa, P. (eds), Fa cies, Tec tonic andTher mal Evo lu tion of the Pom er a nian Sec tor of Trans-Eu ro -pean Su ture Zone and Ad ja cent Ar eas. Prace PañstwowegoInstytutu Geologicznego, 186: 253–269. [In Pol ish, Eng lishab stract].

Grotek, I. 1998. Ther mal ma tu rity of or ganic mat ter in the Zech-stein de pos its of the Pol ish Low lands area. In: Narkiewicz, M. (ed.), Sed i men tary ba sin anal y sis of the Pol ish Low lands.Prace Pañstwowego Instytutu Geologicznego, 165: 255–260.[In Pol ish, Eng lish ab stract].

Grotek, I., 2005. Al ter ation of the coalification de gree of the or -ganic mat ter dis persed in the Car bon if er ous sed i ments alongbor der of the East-Eu ro pean Craton in Po land. Biuletyn Pañs- twowego Instytutu Geologicznego, 413: 5–80. [In Pol ish, En-glish ab stract].


Grotek, I., Matyja, H. & Skompski, S., 1998. Ther mal ma tu rity ofor ganic mat ter in the Car bon if er ous de pos its of the Radom–Lublin and Pomerania ar eas. In: Narkiewicz, M. (ed.), Sed i -men tary ba sin anal y sis of the Pol ish Low lands. Prace Pañs-twowego Instytutu Geologicznego, 165: 245–253. [In Pol ish,Eng lish ab stract].

Hakenberg, M. & Œwidrowska, J., 1997. Prop a ga tion of the SEseg ment of the Pol ish Trough con nected with bound ing faultzones (from the Perm ian to Late Ju ras sic). Commte Rendes de l’Academie Sci ence, Geoscience, 324: 793–803.

Ham il ton, P., Kelley, J. & Fallick, A. E., 1989. K-Ar dat ing ofillite res er voirs. Clay Min er als, 24: 215–232.

Hantschel, T. & Kauerauf, A. I., 2009. Fun da men tals of Ba sin and Pe tro leum Sys tems Mod el ling. Springer, Dordrecht, Hei del -berg, Lon don, New York, 476 pp.

Hunt, J. M., 1979. Pe tro leum Geo chem is try and Ge ol ogy. Free -man and Com pany, San Fran cisco, 743 pp.

Jarzyna, J., Puskarczyk, E., Ba³a, M. & Papiernik, B. 2009. Vari -abil ity of the Rotliegend sand stones in the Pol ish part of theSouth ern Perm ian Ba sin – per me abil ity and po ros ity re la tion -ships. Annales Societatis Geologorum Poloniae, 79: 13–26.

Jubitz, K. B., Znosko, J. & Franke, D., 1986. Tec tonic Map, In ter -na tional Geo log i cal Cor re la tion Programme, Pro ject No 86:South-West Bor der of the East Eu ro pean Plat form. ZentralGeologische Institut, Berlin.

Karnkowski, P., 1993. Z³o¿a gazu ziemnego i ropy naftowej wPolsce, vol. 2. Ni¿ Polski, Wydawnictwo AGH – Geos, Kra-ków, 214 pp. [In Pol ish].

Karnkowski, P., 2003. Car bon if er ous stage of the de vel op mentLublin ba sin as a ma jor stage of hy dro car bon gen er a tion inthe Up per Paleozoik strata – re sults of the mod el ling (Petro-Mod). Przegl¹d Geologiczny, 51: 783–790. [In Pol ish, Eng -lish ab stract].

Karnkowski, P. H., 1996. Ther mal his tory and hy dro car bon gen er -a tion in the area of Dobrzyca Struc ture (West ern Pomerania,Po land). Przegl¹d Geologiczny, 44: 349–357. [In Pol ish, Eng -lish ab stract].

Karnkowski, P. H., 1999. Or i gin and evo lu tion of the Pol ish Rot-liegend Ba sin. Pol ish Geo log i cal In sti tute Spe cial Pa pers, 3:1–93.

Karnkowski, P. H., 2007. Perm ian ba sin as a main ex plo ra tion tar -get in Po land. Przegl¹d Geologiczny, 55: 1003–1015.

Kiersnowski, H., 1997. Depositional de vel op ment of the Pol ishUp per Rotliegend Ba sin and evo lu tion of its sed i ment sourcear eas. Geo log i cal Quar terly, 41: 433–456.

Kiersnowski, H., 1998. Depositional ar chi tec ture of the Rotlie-gend ba sin in Po land. In: Narkiewicz, M. (ed.), Sed i men taryba sin anal y sis of the Pol ish Low lands. Prace PañstwowegoInstytutu Geologicznego, 165: 113–128. [In Pol ish, Eng lishab stract].

Kiersnowski, H. & Buniak, A., 2006. Evo lu tion of the RotliegendBa sin of north west ern Po land. Geo log i cal Quar terly, 50:119–138.

Kiersnowski, H., Paul, J., Peryt, T. M. & Smith, D. B., 1995. Fa -cies, paleogeography and sed i men tary his tory of the South ern Perm ian Ba sin in Eu rope. In: Scholle, P. A., Peryt, T. M. &Ulmer-Scholle, D. S. (eds), The Perm ian of North ern Pangea, 2. Sed i men tary Bas ins and Eco nomic Re sources. Springer,Berlin, pp. 119–136.

Kosakowski, P., Kotarba, M. J., Pomorski, J. & Wróbel, M., 2006.Hy dro car bon po ten tial of the car bon if er ous strata on theKo³obrzeg and Gryfice Blocks (north west ern Po land). 68thEAGE Con fer ence & Ex hi bi tion in cor po rat ing SPE EURO-PEC, 12–15 June, Vi enna. Ex tended Ab stracts CD ROM, As -so ci a tion of Geoscientists & En gi neers, Vi enna.

Kotarba, M. J., Piela, J. & ¯o³nierczuk, T., 1992. Or i gin of gas ac -cu mu la tions in the Perm ian–Car bon if er ous traps of the Pa-proæ field based on iso to pic data. Przegl¹d Geologiczny, 40:260–263. [In Pol ish, Eng lish ab stract].

Kotarba, M. J., Grelowski, C., Kosakowski, P., Wiêc³aw, D., Ko-walski, A. & Sikorski, B., 1999. Hy dro car bon po ten tial ofsource rocks and or i gin of gas acumulations in the Rotliegendand Car bon if er ous in the north ern part of west ern Pomerania.Przegl¹d Geologiczny, 47: 480. [In Pol ish, Eng lish ab stract].

Kotarba, M. J., Clay ton, J. L., Rice, D. D. & Wag ner, M., 2002.As sess ment of hy dro car bon source rock po ten tial of Pol ishbi tu mi nous coals and car bo na ceous shales. Chem i cal Ge ol -ogy, 184: 11–35.

Kotarba, M., Kosakowski, P., Wiêc³aw, D., Grelowski, C., Ko-walski, A., Lech, S. & Merta, H., 2004. Hy dro car bon po ten -tial of Car bon if er ous source rocks on the Bal tic part of Pome-ranian Seg ment of the Mid dle Pol ish Trough. Przegl¹d Geo-logiczny, 52: 1156–1165. [In Pol ish, Eng lish ab stract].

Kotarba, M., Pokorski, J., Grelowski, C. & Kosakowski, P., 2005.Or i gin of nat u ral gases ac cu mu lated in Car bon if er ous andRotliegend strata on the Bal tic part of the West ern Pomerania. Przegl¹d Geologiczny, 53: 425–433. [In Pol ish, Eng lish ab -stract].

Koz³owska, A. & Poprawa, P., 2004. Diagenesis of the Car bon if -er ous clastic sed i ments of the Mazowsze re gion and the nort-hern Lublin re gion re lated to their burial and ther mal his tory.Przegl¹d Geologiczny, 52: 491–500. [In Pol ish, Eng lish ab -stract].

Krzywiec, P., 2002. Mid-Pol ish Trough in ver sion-seis mic ex am -ples, main mech a nisms and its re la tion ship to the Al pine–Carpathian col li sion. In: Bertotti, G., Schulmann, K. & Cloe-tingh, S. (eds), Con ti nen tal col li sion and the tectonosedimen-tary evo lu tion of Fore lands. Eu ro pean Geosciences Un ion.Stephan Mueller Spe cial Pub li ca tion Se ries, 1: 151–165.

Krzywiec, P., 2004. Tri as sic evo lu tion of the K³odawa salt struc -ture: base ment-con trolled salt tec ton ics within the Mid-Pol ish Trough (cen tral Po land). Geo log i cal Quar terly, 48: 123–134.

Krzywiec, P., 2006a. Tri as sic – Ju ras sic evo lu tion of the Pom er a -nian seg ment of the Mid-Pol ish Trough – base ment tec ton icsand sed i men tary pat terns. Geo log i cal Quar terly, 51: 139–150.

Krzywiec, P., 2006b. Struc tural in ver sion of the Pom er a nian andKuiavian seg ments of the Mid-Pol ish Trough – lat eral vari a -tions in tim ing and struc tural style. Geo log i cal Quar terly, 51:151–168.

Kutek, J., 1994. Ju ras sic tec tonic events in south-east ern cratonicPo land. Acta Geologica Polonica, 44: 167–221.

Lamarche, J., Scheck, M. & Lewerenz, B., 2003. Het er o ge neoustec tonic in ver sion of the Mid-Pol ish Trough re lated to crustalar chi tec ture, sed i men tary pat terns and struc tural in her i tance.Tectonophysics, 373: 75–92.

Lee, M., Aronson, J. L. & Savin, S. M., 1995. K-Ar dat ing of timeand gas em place ment in Rotliegende sand stone, The Neth er -lands. Amer i can As so ci a tion of Pe tro leum Ge ol o gists Bul le -tin, 69: 1381–1385.

Liewig, N. & Clauer, N., 2001. K-Ar dat ing of var ied microtex-tural illite in Perm ian gas res er voirs, North ern Ger many. Clay Min er als, 35: 271–281.

Littke, R., 1997. De po si tion of pe tro leum source rocks. In: Welte,D. H. & Horsfield, B. & Baker, D. R. (eds), Pe tro leum andBa sin Evo lu tion. Springer, Dordrecht, Hei del berg, Lon don,New York, pp. 271–334.

Littke, R., Lückge, A., Büker, C., Sachsenhofer, R. F. & Welte, D.H., 1994. A new eval u a tion of palaeo-heat flows and erodedthick nesses for the Car bon if er ous Ruhr ba sin, west ern Ger -

380 D. BOTOR ET AL.

many. In ter na tional Jour nal of Coal Ge ol ogy, 26: 155–183.

Littke, R., Krooss, B. M., Idiz, E. & Frielingsdorf, J., 1995. Mo lec -u lar ni tro gen in nat u ral gas ac cu mu la tions – gen er a tion fromsed i men tary or ganic mat ter at high tem per a tures. Amer i canAs so ci a tion of Pe tro leum Ge ol o gists Bul le tin, 79: 410–430.

Lokhorst, A., 1997. Gas At las of the North-West ern Eu rope.NITG-TNO, The Nedherlands. [CD-room ver sion]

Maækowski, T., 2005. Wp³yw dolnopermskiego wulkanizmu nastopieñ przeobra¿enia termicznego karboñskich ska³ macie-rzystych na obszarze Monokliny Przedsudeckiej, In: Kuœmie- rek, J. (ed.), Sprawozdania z Semianariów Naukowych AGHZSE. AGH, Kraków, pp. 120–122.

Maækowski, T., Papiernik, B., Reicher, B., Stefaniuk, M., Merta,H. & Hajto, M., 1998. Re con struc tion of Lara mide In ver sionin the Cen tral Part of Pol ish Low lands. Ex tended Ab stractsBook, Con fer ence on Mod ern Ex plo ra tion and Im proved Oiland Gas Re cov ery Meth ods. AGH, Kraków, pp. 206–207.

Maækowski, T., Reicher, B., Burzewski, W., Botor, D., Papiernik,B. & Górecki, W., 2008. Rekonstrukcja czasowo-przestrzen-nych parametrów, model ekspulsji i migracji wêglowodoróworaz ocena potencja³u generacyjnego. In: Górecki, W. (ed.),Prog nos tic re sources and un dis cov ered nat u ral gas po ten tialof Rotliegend and Zechstein lime stone de pos its in Po land,Part 5. Un pub lished re port of the pro ject no. 562/2005/Wn-06/FG-sm-tx/D funded by Min is try of En vi ron ment ofPo land in 2005–2008. De part ment of Fos sil Fu els, Fac ulty ofGe ol ogy, Geo phys ics and En vi ron men tal Pro tec tion, AGHUST, Kraków, pp. 1–86. [In Pol ish].

Majorowicz, J. A., Marek, S. & Znosko, J., 1984. Paleogeothermal gra di ents by vitrinite reflectance data and their re la tion to thepres ent geo ther mal gra di ent pat terns of the Pol ish Low land.Tectonophysics, 103: 141–156.

Maliszewska, A., Kuberska, M. & Matyja, H., 2009. Iso to pic in -ves ti ga tions of diagenetic illite of Rotliegend sand stones from the Wielkopolska and west ern Pomerania re gions. Przegl¹dGeologiczny, 57: 322–327. [In Pol ish, Englis ab stract]

Marek, S. & Pajchlowa, M., 1997. The epicontinental Perm ian and Me so zoic in Po land. Prace Pañstwowego Instytutu Geolo-gicznego, 153, pp. 1–284. [In Pol ish, Eng lish sum mary].

Matyasik, I., 1998. Geo chem i cal char ac ter is tics of the Car bon if er -ous source rock in the se lected bore holes in the Radom–Lublin and Pomerania ar eas. In: Narkiewicz, M. (ed.), Sed i -men tary ba sin anal y sis of the Pol ish Low lands. Prace Pañs-twowego Instytutu Geologicznego, 165: 215–226. [In Pol ish,Eng lish ab stract].

Matyja, H., 2006. Stra tig ra phy and fa cies de vel op ment of De vo -nian and Car bon if er ous de pos its in the Pom er a nian Ba sin andin the west ern part of the Bal tic Ba sin and paleogeography ofthe north ern TESZ dur ing Late Pa leo zoic times. In: Matyja,H. & Poprawa, P. (eds), Fa cies, Tec tonic and Ther mal Evo lu -tion of the Pom er a nian Sec tor of Trans-Eu ro pean Su tureZone and Ad ja cent Ar eas. Prace Pañstwowego Instytutu Geo- logicznego, 186: 79–122. [In Pol ish, Eng lish ab stract].

Mazur, S., Scheck-Wenderoth, M. & Krzywiec, P., 2005. Dif fer -ent modes of the Late Cre ta ceous–Early Ter tiary in ver sion inthe North Ger man and Pol ish bas ins. In ter na tional Jour nal ofEarth Sci ences, 94: 782–798.

Mazur, S., Dunlap, W. J., Turniak, K. & Oberc-Dziedzic, T.,2006a. Age con straints for the ther mal evo lu tion and ero -sional his tory of the cen tral Eu ro pean Variscan belt: new datafrom the sed i ments and base ment of the Car bon if er ous fore -land ba sin in west ern Po land. Jour nal of the Geo log i cal So ci -ety, Lon don, 163: 1011–1024.

Mazur, S., Aleksandrowski, P., Kryza, R. & Oberc-Dziedzic, T.,2006b. The Variscan Orogen in Po land. Geo log i cal Quar -

terly, 50: 89–118.

Mazur, S., Aleksandrowski, P., Turniak, K., Krzemiñski, L., Ma-stalerz, K., Rundach, A., Górecka-Nowak, A., Kurowski, L.,Krzywiec, P., ¯elaŸniewicz, A., & Fan ning, M. C., 2010. Up -lift and late orogenic de for ma tion of the Cen tral Eu ro peanVariscan belt as re vealed by sed i ment prov e nance and struc -tural re cord in the Car bon if er ous fore land ba sin of west ernPo land. In ter na tional Jour nal of Earth Sci ences (Geologische Rundschau), 99: 47–64.

McCann, T., Pascal, C., Timmerman, M. J., Krzywiec, P., Lopez-Gomez, J., Wetzel, A., Krawczyk, C. M., Rieke, H., & La-marche, J., 2006. Post-Variscan (end Car bon if er ous–EarlyPerm ian) ba sin evo lu tion in West ern and Cen tral Eu rope. In:Gee, D. G. & Stephenson, R. A. (eds), Eu ro pean Litho sphereDy nam ics. Geo log i cal So ci ety, Lon don, Mem oirs, 32: 355–388.

Michalik, M., 2002. Diagenesis of the Weis Sand stone (LowerPerm ian) in the Fore-Sudetic Monocline. Prace Mineralo-giczne, 157: 1–245.

Narkiewicz, M., 2007. De vel op ment and in ver sion of De vo nianand Car bon if er ous bas ins in the east ern part of the Variscanfore land (Po land). Geo log i cal Quar terly, 51: 231–256.

Niedbalec, S. & Radecki, S., 2007. Hy dro car bon ac cu mu la tions inPo land. Przegl¹d Geologiczny, 55: 985–991.

Nowak, G., 2003. Petrologia materii organicznej rozproszonej wosadach póŸnopalezoicznych SW Polski. Cu prum, 29: 1–221. [In Pol ish].

Nowak, G., 2007. Com par a tive stud ies of or ganic mat ter pe trog ra -phy of the Late Palaeozoic black shales from south west ernPo land. In ter na tional Jour nal of Coal Ge ol ogy, 71: 568–585.

Papiernik, B. & Reicher, B., 1998. The nu mer i cal 3-D res to ra tionof the Lara mide up lift mag ni tude in the cen tral part of the Pol -ish Low lands. Ex tended Ab stracts Book, Con fer ence on Mod -ern Ex plo ra tion and Im proved Oil and Gas re cov ery Me-thods, AGH, Kraków, pp. 175–176.

Papiernik, B., Buniak, A., Hajto, M., Kiersnowski, H., Zych, I.,Machowski, G. & Jasnos, J., 2008. Model pojemnoœciowyutworów czerwonego sp¹gowca i wapienia cechsztyñskiegona podstawie laboratoryjnych badañ petrofizycznych i inter-pretacji geofizyki wiertniczej. In: Górecki, W. (ed.), Prog -nos tic Re sources and Un dis cov ered Nat u ral Gas Po ten tial ofRotliegend and Zechstein Lime stone De pos its in Po land, Part 3. Re port of the pro ject no. 562/2005/Wn-06/FG-sm-tx/Dfunded by Min is try of En vi ron ment of Po land in 2005–2008.De part ment of Fos sil Fu els, Fac ulty of Ge ol ogy, Geo phys icsand En vi ron men tal Pro tec tion, AGH UST, Kraków, pp. 1-169. [In Pol ish].

Papiernik, B., Górecki, W. & Pasternacki, A., 2010. Pre lim i naryre sults of 3D mod el ing of petrophysical pa ram e ters for tightgas pros pect ing in the Pol ish Rotliegend Ba sin. Przegl¹dGeologiczny, 58: 352–364. [In Pol ish, Eng lish ab stract].

Papiernik, B., Kiersnowski, H., Machowski, G. & Górecki, W.,2012. Up per Rotliegend res er voir and fa cies mod els of geo-mor pho log i cal and struc tural gas traps in Silesian Ba sin –South-West Po land. Ex tended Ab stracts, 74th EAGE Con fer -ence & Ex hi bi tion in cor po rat ing SPE EUROPEC, 4–7 June,Co pen ha gen. EarthDoc, EAGE Pub li ca tions B.V. http://www.earthdoc.org/pub li ca tion/publicationdetails/?pub li ca -tion = 59497 [30.12.2013].

Pe ters, K. E. & Cassa, M. R., 2002. Ap plied source rock geo chem -is try. Mem oir Amer i can As so ci a tion Pe tro leum Ge ol o gists,60: 93–120.

Piwocki, M. 2004. Paleogen. In: Peryt, T. & Piwocki, M. (eds),Ge ol ogy of Po land, Vol. I, Stra tig ra phy, Part. 3a, Caino zo ic,Paleogene i Neo gene. Panstwowy Instytut Geologiczny,


Warszawa, pp. 22–71. [In Pol ish, Eng lish ab stract].Pletsch, T., Ap pel, J., Botor, D., Clay ton, C. J., Duin, E. J. T.,

Faber, E., Górecki, W., Kombrink, H., Kosakowski, P., Ku-per, G., Kus, J., Lutz, R., Mathiesen, A., Ostertag-Henning,C., Papiernik, B. & Van Bergen, F., 2010. Pe tro leum gen er a -tion and mi gra tion. In: Doornenbal, J. C. & Stevenson, A. G.(eds), Pe tro leum Geo log i cal At las of the South ern Perm ianBa sin Area. EAGE Pub li ca tions, Houten, pp. 225–253.

Plewa, F., 1994. Rozk³ad parametrów geotermalnych na obszarzePolski. Wydawnictwo Centrum Podstawowych ProblemówGospodarki Surowcami Mineralnymi i Energi PAN, Kraków,138 pp. [In Pol ish].

Poelchau, H. S., Baker, D. R., Hantschel, T., Horsfield, B. &Wygrala, B., 1997. Ba sin sim u la tion and de sign of the con -cep tual model. In: Welte, D. H., Horsfield, B. & Baker, D. R.(eds), Pe tro leum and Ba sin Evo lu tion. Springer, Dordrecht,Hei del berg, Lon don, New York, pp. 3–70.

Pokorski, J., 1998. Mapa: Paleogeografia póŸnego czerwonegosp¹gowca. Podgrupa Noteci. In: Dadlez, R., Marek, S. &Pokorski, J. (eds), At las paleogeograficzny epikontynental-nego permu i mezozoiku w Polsce. Pañstwowy Instytut Geo-logiczny, Warszawa. [In Pol ish].

Pokorski, J., 2008. Schematyczna mapa rozmieszczenia utworówkarbonu dolnego i górnego z okreœleniem litofacji dominu-j¹cych. In: Górecki, W. (ed.), Prog nos tic re sources and un -dis cov ered nat u ral gas po ten tial of Rotliegend and Zechsteinlime stone de pos its in Po land, Part 2. Re port of the pro ject no. 562/2005/Wn-06/FG-sm-tx/D funded by Min is try of En vi -ron ment of Po land in 2005–2008. De part ment of Fos sil Fu els, Fac ulty of Ge ol ogy, Geo phys ics and En vi ron men tal Pro tec -tion, AGH UST, Kraków. [In Pol ish].

Poprawa, P., 1997. Late Perm ian to Ter tiary dy nam ics of the Pol -ish Trough. Terra Nos tra, 97/11: 104–109.

Poprawa, P., 2010. Anal y sis of shale gas po ten tial of siltstone andmudstone for ma tions in Po land. Biuletyn Pañstwowego Insty- tutu Geologicznego, 439: 159–172. [In Pol ish, Eng lish ab -stract].

Poprawa, P. & Andriessen, P., 2006. Ap a tite fis sion track thermo-chro nol ogy of the north ern and cen tral part of the Pol ish Ba -sin – pre lim i nary re sults. In: Matyja, H. & Poprawa, P. (eds),Fa cies, Tec tonic and Ther mal Evo lu tion of the Pom er a nianSec tor of Trans-Eu ro pean Su ture Zone and Ad ja cent Ar eas.Prace Pañstwowego Instytutu Geologicznego, 186: 271–292.[In Pol ish, Eng lish ab stract].

Poprawa, P. & Kiersnowski, H., 2008. Po ten tial for shale gas andtight gas ex plo ra tion in Po land. Biuletyn Pañstwowego Insty-tutu Geologicznego, 429: 145–152. [In Pol ish, Eng lish ab -stract].

Poprawa, P. & Kiersnowski, H., 2010. Tight gas res er voirs in Po -land. Biuletyn Pañstwowego Instytutu Geologicznego, 439:173–180. [In Pol ish, Eng lish ab stract].

Poprawa, P., Grotek I., Wag ner M. & Matyja H., 2002. Phane-rozoic ther mal his tory of the Pol ish Trans-Su ture Zone. Prze-gl¹d Geologiczny, 50: 1219–1220. [In Pol ish, Eng lish ab -stract].

Poprawa, P., Grotek, I. & ̄ ywiecki, M., 2005. Im pact of the Perm -ian mag matic ac tiv ity on the ther mal mat u ra tion of the Car -bon if er ous sed i ments in the outer Variscan orogen (SW Po-land). Min er al og i cal So ci ety of Po land Spe cial Pa pers, 26:255–260.

Po¿aryski, W., Grocholski, A., Tomczyk, H., Karnkowski, P. &Moryc, W., 1992. Tec tonic map of Po land dur ing theVariscan time. Przegl¹d Geologiczny, 40: 643–651. [In Pol -ish, Eng lish ab stract].

Protas, A., Ha³as, S. & Wójtowicz, A., 2006. Datowanie K-Ar

illitu w utworach czerwonego sp¹gowca na Ni¿u Polskim. In:Materia³y IX Konferencji: Datowanie Ska³ i Minera³ów,Gdañsk, 23–24 X. 2006. Uniwersytet Gdañski, Gdañsk, p.123. [In Pol ish].

Reicher, B., 2008. The el e ments of the Car bon if er ous-Perm ian pe -tro leum sys tem in the Pol ish Low lands. In: Górecki, W. (ed.),Prog nos tic Re sources and Un dis cov ered Nat u ral Gas Po ten -tial of Rotliegend and Zechstein Lime stone De pos its in Po -land, Part 5. Re port of the pro ject no. 562/2005/Wn-06/FG-sm-tx/D funded by Min is try of En vi ron ment of Po land in2005–2008. De part ment of Fos sil Fu els, Fac ulty of Ge ol ogy,Geo phys ics and En vi ron men tal Pro tec tion, AGH UST Kra-ków, [In Pol ish].

Resak, M., Narkiewicz, M. & Littke, R., 2008. New ba sin mod el -ling re sults from the Pol ish part of the Cen tral Eu ro pean Ba sin sys tem (Pomerania): im pli ca tions for the Late Cre ta ceous–Early Paleogene struc tural in ver sion. In ter na tional Jour nal of Earth Sci ences, 97: 955–972.

San Leon En ergy, 2013. SW Car bon if er ous Ba sin. http://www.sanleonenergy.com/op er a tions-and-as sets/sw-car bon if er ous-ba sin.aspx [30.12.2013].

Scheck-Wenderoth, M. & Lamarche, J., 2005. Crustal mem oryand ba sin evo lu tion in the Cen tral Eu ro pean Ba sin Sys tem –new in sights from a 3D struc tural model. Tectonophysics,397: 143–165.

Schlumberger, 2013a. PetroMod Pe tro leum Sys tems Mod el ingSoftware. http://www.soft ware.slb.com/prod ucts/foun da tion/Pages/petromod.aspx [30.12.2013].

Schlumberger, 2013b. Pe trel Ex plo ra tion & Pro duc tion Soft warePlat form. http://www.soft ware.slb.com/prod ucts/plat form/Pages/pe trel.aspx [30.12.2013].

Schwarzer, D. & Littke, R., 2007. Pe tro leum gen er a tion and mi -gra tion in the ‘Tight Gas’ area of the Ger man Rotliegend nat -u ral gas play: a ba sin mod el ling study. Pe tro leum Geo-sci ence, 13: 37–62.

Senglaub, Y., Littke, R. & Brix, M. R., 2006. Nu mer i cal mod el -ling of burial and tem per a ture his tory as an ap proach for anal ter na tive in ter pre ta tion of the Bramsche anom aly, LowerSax ony Ba sin. In ter na tional Jour nal of Earth Sci ences, 95:204–224.

S³owakiewicz, M. & Miko³ajewski, Z., 2011. Up per Perm ianMain Do lo mite mi cro bial car bon ates as po ten tial source rocks for hy dro car bons (W Po land). Ma rine and Pe tro leum Ge ol -ogy, 28: 1572–1591.

Speczik, A. & Koz³owski, A., 1987. Fluid in clu sion study ofepigenetic veinlets from the Car bon if er ous rocks of the Fore-Sudetic monocline (SW Po land). Chem i cal Ge ol ogy, 61:287–298.

Stefaniuk, M., Baranowski, P., Czopek, B. & Maækowski, T.,1996. Study of com pac tion in the Pom er a nian AnticlinoriumArea. Oil and Gas News from Po land, 6: 150–162.

Stephenson, R. A., Narkiewicz, M., Dadlez, R., Van Wees, J.-D. & Andriessen, P., 2003. Tec tonic sub si dence mod el ling of thePol ish Ba sin in the light of new data on crustal struc ture andmag ni tude of in ver sion. Sed i men tary Ge ol ogy, 156: 59–70.

Swee ney, J. J. & Burnham, A. K., 1990. Eval u a tion of a sim plemodel of vitrinite reflectance (EASY%Rr) based on chem i calki net ics. Amer i can As so ci a tion Pe tro leum Ge ol o gists Bul le -tin, 74: 1559–1570.

Szewczyk, J. & Gientka, D., 2009. Ter res trial heat flow den sity inPo land – a new ap proach. Geo log i cal Quar terly, 53: 125–140.

Van Wees, J.-D., Stephenson, R. A. & Ziegler, P. A., 2000. On theor i gin of the South ern Perm ian Ba sin, Cen tral Eu rope. Ma -rine and Pe tro leum Ge ol ogy, 17: 43–59.

382 D. BOTOR ET AL.

Wag ner, R., 1998. Zechstein. In: Dadlez, R., Marek, S., & Po-korski, J. (eds), Palaeogeographic At las of EpicontinentalPerm ian and Me so zoic in Po land (1: 2 500 000). Pol ish Geo -log i cal In sti tute, Warszawa.

Wag ner, M., 1999. Vitrinite Reflectance in Se lected Bore holesfrom the Pol ish Ba sin (Pol ish Low land). Un pub lished re port,Pol ish Geo log i cal In sti tute Ar chive, War saw, 89 pp.

Waples, D., Kamata, H. & Suizu, M., 1992. The art of the ma tu rity mod el ing – over view of meth ods. Amer i can As so ci a tion Pe -tro leum Ge ol o gists Bul le tin, 76: 31–46.

Warr, L. N., Prim mer, T. J. & Rob in son, D., 1991. Variscan verylow grade meta mor phism in SW Eng land: a diastathermal and thrust-re lated or i gin. Jour nal of Meta mor phic Ge ol ogy, 9:751–764.

Wierzchowska-Kicu³owa, K., 1984. Ge ol ogy of the pre-Perm ianse ries of the Fore-Sudetic Monocline. Geologica Sudetica,19: 121–142. [In Pol ish, Eng lish ab stract].

Witkowski, A. & ¯elichowski, A. M., 1981. Geo log i cal Struc tureof the Sub-Perm ian Rocks in the North ern part of the Fore-Sudetic Homocline. Ar chive of the Pol ish Geo log i cal In sti -tute, Warszawa, p. 88. [Un pub lished, in Pol ish].

Wygrala, B. P., 1989. In te grated study of an oil field in the south -ern Po Ba sin, north ern It aly. Berichte der Kernforschungs-

anlage Julich, 2313: 1–217.Yalcin, M. N., Littke, R. & Schsenhofer, R. F., 1997. Ther mal his -

tory of sed i men tary bas ins. In: Welte, D. H., Horsfield, B., &Baker, D. R. (eds) Pe tro leum and Ba sin Evo lu tion. Springer,Dordrecht, Hei del berg, Lon don, New York, pp. 71–168.

Zdanowski, A. & ¯akowa, H., 1995. The Car bon if er ous sys tem inPo land. Prace Pañstwowego Instytutu Geologicznego, 148:1–215.

Ziegler, P. A., Bertotti, S. & Cloetingh, S., 2002. Dy namic pro -cesses con trol ling fore land de vel op ment – the role of me -chan i cal (de)cou pling of orogenic wedges and fore lands.EGU Stephan Mueller Spe cial Pub li ca tion Se ries, 1: 17–56.

¯elichowski, A. M., 1964. Utwory karbonu w pod³o¿u monoklinyprzedsudeckiej. Przegl¹d Geologiczny, 12: 224–227. [In Pol -ish].

¯elichowski, A. M., 1980. Syn op tic pro file of Car bon if er ous inthe sub stra tum of the Fore-Sudetic Monocline. KwartalnikGeologiczny, 24: 942–943.

¯elichowski, A. M., 1995. Lithostratigraphy and sedimentologic-paleogeographic de vel op ment. Cen tral Po land and Wielko-polska re gions. In: Zdanowski, A. & ¯akowa, H. (eds), TheCar bon if er ous sys tem in Po land. Prace Pañstwowego Insty-tutu Geologicznego, 148: 100–102 and 148–151.


gas gen er a tion in car bon if er ous source rocks of the variscan

Documents