contributions to the paleozoic evolution of northern...

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CONTRIBUTIONS TO THE PALEOZOIC EVOLUTION OF NORTHERN THAILAND

Helmcke, D.Department of Applied Geology and Remote Sensing, GZG, University of Goettingen, Germany

Chonglakmani, C.School of Geotechnology, Suranaree University of Technology

Feng, Q.Faculty of Earth Sciences, China University of Geosciences, Wuhan, P.R. of China

Ingavat-Helmcke, R.Department of Applied Geology and Remote Sensing, GZG, University of Goettingen, Germany

AbstractWhen the geodynamic evolution of Northern Thailand and the question of possibly Gondwana

derived terranes is discussed, then the tectonic model including a cryptic suture of Triassic age betweenthe “Inthanon zone” and the “Sukhothai zone” proposed by Barr and Macdonald (1991) is of specialinterest. Data obtained during recent field work in Northern Thailand and Southern Yunnan (P.R. ofChina) revealed, however, that more data on the Paleozoic evolution of this region are needed to unravelthe long lasting geodynamic history.

During the past years it could be proved that a zone containing Triassic radiolarian cherts mayextend from the Fang-Chiang Dao region to the area fo Lamphun and may extend even further ot theSouth (Caridroit, 1993, Caridroit et al., 1992, Sashida et al., 2000, Feng et al., 2002). It may be speculatedthat these deep-water sediments of Triassic age can be interpreted as possible indications of a crypticsuture of Triassic age in this region (Barr and Macdonald, 1991, Fig. 3 place this cryptic suture somewhatfurther east). Other geological data from Northern Thailand and southwestern Yunnan, however, areapparently not substantiating this interpretation. In this contributiojn we like to concentrate on thesecontradictions. First we mention some features of the Khuntan Range as exposed for example along thehighway Chiang Mai – Lampang and then we compare these features with data from the Lancang JiangZone in southern Yunnan (.P.R. of China) recently published (Helmcke et al., 2001).

Published in Geodynamic Processes of Gondwana-derived Terranes in East and Southeast Asia, 2002.

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DESIGN GUIDELINE FOR SALT SOLUTION MINING IN THAILAND

Kittitep FuenkajornSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

AbstractA general guideline has been developed for the design of salt solution-mined caverns in Sakon

Nakorn and Khorat basins. Laboratory testing calibrates the mechanical and rheological properties of thesalt formation. Via a series of numerical analyses, conservative configurations of the solution minecaverns are determined. It is recommended that the caverns be arranged in an array of single well systemand should have the maximum diameter and height of 80 m and 60 m, respectively. The minimum spacingis estimated to be 240 m. The cavern field would yield an extraction ratio of 1.96 x 106 m3 of rock salt perone square kilometer. The salt roof and floor should be greater than 200 m to prevent excessive movementof the cavern ground.

ตีพิมพในวิศวกรรมสาร ฉบับวิจัยและพัฒนา ปที่ 13 ฉบับที่ 1 2545

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MODIFIED POINT LOAD TEST FOR DETERMINING UNIAXIAL COMPRESSIVESTRENGTH OF INTACT ROCKS

Kittitep FuenkajornSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

AbstractA modified point load (MPL) testing technique is proposed to correlate the results with the

uniaxial compressive strength (UCS) of intact rocks. The test apparatus is similar to that of theconventional point load (CPL), except that the loading points are cut flat to have a circular cross-sectionalarea instead of using a half-spherical shape. The load is applied along the axis of cylindrical (disk)specimens. The results from finite element analysis suggest that the applied stress required to fail the MPLspecimen increases logarithmically as the specimen thickness or diameter increases. The maximum tensilestress occurs directly below the loading area with a distance approximately equal to the loading diameter.Over 400 specimens of Saraburi marble have been tested to determine the compressive strength and theMPL and CPL strength index under a variety of specimen sizes and length-to-diameter ratios. The testresults suggest that the MPL strength can be correlated with the UCS when the MPL specimens arerelatively thin, and can be an indicator of the tensile strength when the specimens are significantly largerthan the diameter of the loading points. Even though both MPL and CPL tests overestimate the actualUCS of the rocks, the MPL results yield a better correlation than does the CPL strength index.

Published in NARMS-TAC 2002, Hammah et al. (eds), University of Toronto, 2002.

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SLOPE FAILURE ALONG LOMSAK-CHUMPAE HIGHWAY, THAILAND

K. Fuenkajorn and P. ThongthiangdeeSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

AbstractField examination and limit equilibrium analyses have been performed to identify the failure

characteristics of four rock slopes along Lomsak-Chumpae highway. The failure mechanisms are intricatedue to the heterogeneity of the materials, the irregularity of the slope profile, and the fluctuation ofgroundwater in the rock mass and the overlying soil. Various combinations of the modes of failure havebeen found, e.g., plane and wedge slides, block toppling, and circular failure, Rapid weathering has beenthe cause for the initial and minor failures. These progressive failures normally associated with heavyrainfall. Such factors had not been taken into consideration in the original slope design and in the laterstabilization schemes. As a result, inappropriate stabilization methods and been implemented, whichsubsequently contributed to the recent massive failure. A computerized expert system has been used todetermine a new stabilization scheme. If recommends that further failure may be prevented by using fullygrouted rock bolts, small opening wire mesh, and long drained pipes. Shotcrete should be avoided.

Published in the 3th International Conference on Landslides, Slope Stability & the Safety ofInfrastructures, Singapore, July 11-12, 2002.

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PETROLEUM PRODUCTION EFFICIENCY IN CARBONATE RESERVOIR

Kriangkrai TrisarnSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

AbstractSUT budget, laboratories, and personnel supported this project with the assistant from DMR

personnel for data and reservoir simulation. The objective of the research is to study and estimate thepetroleum production efficiency in carbonate rock reservoir, especially for gas reservoir in the northeast ofThailand. In the past, the petroleum production efficiency estimation could not performed accurately andsufficiently enough due to the data from the concessionaire is limited and confidential. Therefore, it isnecessary to study the distribution of porosity and permeability in carbonate rock. The porosity andpermeability data has been compiled from literature reviews such as concessionaire results, technical, andconference papers. More than 30 carbonate rock samples were collected from the fields to measure theporosity and permeability in SUT laboratory. The exploration in the NE area was at 10% risk, the FASPUprogram was run and resulted as the most likely potential reservoir gas inplace at 255 Bcf. Three gasinplace size models were simulated for economic evaluation aspect. The tank model reservoir programwas developed to compare the reservoir simulation results. For the 255 Bcf gas inplace models reservoirsimulation, the gas production rate is started with 90 MMSCF/D and lasted for two years then declinedabout 16% per year until ended at the 20th year, with the final rate of 5 MMSCFD. The economic analysisof the production of this case was done and given 20% rate of return with PIR of 1. The benefit of thisstudy will improve the knowledge of reservoir simulation model including the ability to use the softwarefor petroleum production efficiency approximation and probably promote the petroleum activities in thearea.

Published in the Proceeding of the 6th PTTEP Technical Forum, Rajpruek Club, August 1-2, 2002.

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GEODYNAMIC EVOLUTION OF LOEI AND PHETCHABUN REGIONS-DOES THEDISCOVERY OF DETRITAL CHROMIAN SPINELS FROM THE NAM DUK FORMATION

(PERMIAN, NORTH-CENTRAL THAILAND) PROVIDE NEW CONSTRAINT

Chongpan ChonglakmaniSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

Dietrich HelmckeInstitute of Geology and Dynamics of the Lithosphere, University of Goettingen

AbstractThe discovery of the chromian spinel detritus in sandstones from the Permian Nam Dak

Formation (Phetchabun region) confirms that the siliciclastic part of this formation is related to the erosionof a mountain belt caused by compressional deformation. The question discussed is whether this detritus isderived from an older orogen exposed today in the region of Loei east of the Nam Duk Basin, or it is froma mountain belt which evolved during Permian times in the west (Nan-Uttaradit region).

In the first case the Nam Duk Formation would represent the passive continental margin sequenceof the “Indochina craton”, and in the second case it would be part of the sedimentary wedge associatedwith the compressional deformation and subsequent uplift to the erosional level during Middle to UpperPermian of a rising mountain belt further in the west. In this contribution, arguments in favour of thesecond scenario are discussed. The region close to the Nan-Uttaradit suture zone shows evidence ofcompressional deformation and subsequent uplift to an erosional level in the Permian when the chromianspinel detritus was deposited in the Nam Duk Formation.

Published in International Association for Gondwana Research, Vol. 4, No. 3, 2001.

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THE SARABURI GROUP OF NORTH-CENTRAL THAILAND: IMPLICATION FORGEOTECTONIC EVOLUTION

Chongpan ChonglakmaniSchool of Geotechnology, Suranaree University of Technology

AbstractThe Permian sequences, consisting predominantly of thick carbonate sediments, are distributed

extensively in Thailand. They were well known as the Ratburi Limestone with its type area in theRatchaburi province, western Thailand (Brown et al., 1951). Subsequent works in northern andnortheastern Thailand led Bunopas (1981) to doubt the correlation of the limestone units found in theseregions with those of the type area. He proposed the names Ngao and Saraburi Groups for the Permianlimestones in northern and northeastern Thailand respectively. It is now widely accepted that the RatburiGroup, based on its faunal content, is quite different from the comparable limestone units in the north andnortheast. The former belongs to the sediments deposited in the peri-Gondwana realm, whereas the lattertwo belong to the Tethyan realm (Ueno, 1999).

In Phetchabun fold-belt of north-central Thailand, a complex geosynclinal clastic-carbonatesequence (Nam Duk Formation) of Early-Middle Permian age was differentiated from the shelf sequence(Pha Nok Khao Limestone and Hua Na Kham Formation) found further to the east (Chonglakmani andSattayarak, 1978). The deep sea Permian sediments have been confirmed and studied in more detail bysubsequent investigations (Winkel et al., 1983; Wielchowsky and Young, 1985; Altermann, (1989).

In the Saraburi area about 300 km. south of Phetchabun province, the Permian Saraburi Groupwas subdivided into the Sap Bon, the Khao Khad, the Pang Asok, the Nong Pong, the Khao Khwag, andthe Phu Phe Formations respectively in descending order. These range in age from Early to early LatePermian (Hinthong et al., 1976). Detailed study of the Saraburi Group in the Saraburi-Pak Chong areaallows the recognition of various facies belts representing the shelf or platform, basin margin and deepbasin environments. Platform facies consist predominantly of medium-to thick-bedded skeletalgrainstones, packstones and wackestones of open shelf environment. Laminated micrites and dolomitesrepresenting the inner shelf are also present. The platform facies comprise the Phu Phe, the Khao Khad,and the Khao Khwang Formations. Slope or basin margin facies is represented by the Sap Bon, the PangAsok and part of the Nong Pong Formation. They form a thick succession of bioclastic grainstones andpackstones, tempestites, limestone breccias and conglomerates, allodapic limestones, siliciclastics and

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chert. Hummocky cross-bedding is common in grainstones of the upper slope particularly in the newlyestablished Khzo Phaeng Ma Formation. The deep basin or basin plain facies are characterized mainly byfine-grained sediments. They consist of thin-bedded shales, cherts, argillaceous micrites and allodapiclimestones which are typical of the Nong Pong Formation.

The investigated area is structurally complex and belongs to the Loei-Phetchabun fold-belt. Manykarstic terrains characterized by the shelf or platform facies are considered to be allochthonous based onstratigraphic, paleontologic, sedimentologic and structural evidences. No true oceanic crust is found in theSaraburi basin suggesting that the basin is relatively narrow and is not a true deep basin. Tectonically, thearea including the Phetchabun fold-belt is part of a back-arc basin with a foreland area lying further to theeast.

Published in Gondwana Research, Vol. 4, 2001.

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TERTIARY FLORAS OF NORTHERN THAILAND: CHARCOALIFIED CONIFER WOOD

Grote, Paul J. and Pramook BenyasutaSchool of Biology, Institute of Science, Suranaree University of Technology


AbstractInvestigations have been made in charcoalified wood fragments from the remains of a presumed

ancient forest fire at Li Basin, Lamphun Province, Northern Thailand, and thought to be of Late Oligoceneor Miocene age. The wood fragments are situated on a thick layer of lignite in the Ban Pu Subbasin of theLi Basin, one of many Tertiary basins extending from Northern Thailand, along the Malay Peninsula, toJava and Sumatra. All wood fragments observed are from conifers. The wood occurs as thin, tangentiallycompressed fragments, up to approximately 3 cm long. Tracheids are long and slender (>1.7 mm lengthby 21-58 micrometers width). Bordered pits are arranged in a single row or rarely in 2 opposite rows onradial and tangential walls of the tracheids. Axial parenchyma and resin canals were not observed. Raysare uniseriate, homocellular, reach a height of >40 cells, consist of parenchyma cells, and lack raytracheids. Crossfields show one bordered pit in the tracheid wall, bordered pits not occurring in the raycells. Presence or absence of annual rings could not be determined. The wood is assigned to the formgenus Podocarpoxylon, with possible affinity to Podocarpaceae. The presence of these charcoalifiedramains may indicate a period in which the lignite forming swamp dired, at least locally, and supported agrove of conifers subject to forest fire.

Published in Botany, Plants, and People, Albuquerque, New Mexico, U.S.A., August 12-16, 2001.

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ROCK SLOPE DESIGN USING EXPERT SYSTEM: ROSES PROGRAM

Kittitep Fuenkajorn and Santhat KamutchatSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

AbstractA computerized expert system (called ROSES) has been developed to assist in the stability

evaluation and support design of rock slopes. The system shell uses Visual Prolog to make it user-friendly,interactive and revisable. The system is designed for man-made and natural rock slopes under a variety ofgeological conditions and engineering requirements. The inference engine employs forward chainingstrategy by collecting data, categorizing the slope to fit the preset conditions, evaluating the stability, andseeking the most appropriate design recommendation. The main input data include the general geologicalfeatures, slope applications, water conditions, slope geometry, rock types, discontinuity characteristics,engineering constraints, geomechanics parameters, degrees of weathering, and vegetation. The consideredmodes of failure are plane sliding, wedge failure, toppling, and circular failure. The system has beensubjected to tests using real mining situations and comparing with textbook solutions. The results areencouraging.

Published in the 6th Mining, Metallurgical, and Petroleum Engineering Conference, Bangkok, 2001.

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ROCK SALT FORMATIONS AS POTENTIAL NUCLEAR WASTE REPOSITORY

Kittitep Fuenkajorn and Khomkrit WetchasatSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

AbstractA series of laboratory testing and numerical simulations have been carried out to assess the

mechanical performance of the rock salt formations for the potential nuclear waste disposal in Thailand.Uniaxial creep tests and stress-controlled tests determine the mechanical and rheological properties(strength, elastic, visco-elastic and visco-plastic parameters) of rock salt specimens obtained from UdonThani. Based on the existing borehole information, five geologically favorable areas in Sakon Nakorn andKhorat basins are assumed as tentative repository sites. The computer modeling uses the laboratory-calibrated properties to simulate the time-dependent stress, strain and deformation around the salt cavern,as well as the movement of the overlying formations. The design emphasizes the mechanical stabilityunder isothermal conditions during the waste emplacement (currently aimed at 50 years), and the long-term isolation for the next 500 years. The preliminary results from the area of Ban Kudjig, Wanon Niwatdistrict, Sakon Nakorn province (one of the selected areas) suggest that long-term stability of the disposedcaverns may be achieved if suitable design configurations have been implemented. The caverns should besolution-mined below 585 meters depth. The minimum diameter of the spherical shaped cavern should be40 meters (equivalent to 25,133 m3). The minimum salt roof and floor are 200 meters. The surfacesubsidence is calculated to be less than one cm through the next 500 years, providing that the internalpressure is maintained to be equivalent to the hydrostatic pressure of saturated brine.


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SIZE AND STRESS GRADIENT EFFECTS ON THE MODIFIED POINT LOADSTRENGTHS OF SARABURI MARBLE

Kittitep Fuenkajorn and Prachya TepnarongSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

AbstractA modified point load (MPL) testing technique is proposed to correlate the results with the

uniaxial compressive strength and tensile strength of intact rock. The test apparatus is similar to that of theconventional point load (CPL), except that the loading points are cut flat to have a circular cross-sectionalarea instead of using a half-spherical shape. Diameters of the loading point vary from 5, 10, 15, 20, 25, to30 mm. This results in a new loading and boundary conditions on the rock specimens that mathematicallyallow correlating its results with those of the standard testing. To derive a new solution, finite elementanalyses and laboratory experiments have been caried out. For this early stage of development, the MPLspecimens and models are taken as a circular disk. The simulation results suggest that the applied stressrequired to fail the MPL specimen increases logarithmically as the specimen thickness or diameterincreases. The minimum tensile stress occurs directly below the loading area with a distanceapproximately equal to the loading diameter. The MPL tests, CPL tests, uniaxial compressive strengthtests and Brazilian tensile strength tests have been performed. Over 400 specimens of Saraburi marblehave been prepared and tested under a variety of diameter and thickness (or length). The uniaxial testresults indicate that the strengths decrease with increasing length-to-diameter ratio. The Brazilian tensilestrengths also decrease as the specimen diameters increase. Post-faulure observations on the specimensalso suggest that shear failure is predominant when the specimens thickness is less than twice the loadingdiameter while extension failure is predominant when the specimens are thicker than three times theloading diameter. This can be postulated that the MPL strength can be correlated with the compressivestrength when the MPL specimens are relatively thin, and should be an indicator of the tensile strengthwhen the specimens are significantly larger than the diameter of the loading points. Even though bothMPL and CPL tests overestimate the uniaxial compressive strength of the rock, the MPL results yield abetter correlation than does the CPL strength index. The rock tensile strength predicted by the MPL testingis about twice the Brazilian tengile strength.


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CORRELATION OF TECTONO-STRATIGRAPHIC UNITS IN NORTHERN THAILAND WITHTHOSE OF WESTERN YUNNAN (CHINA)


Feng QinglaiFaculty of Earth Sciences, China University of Geosciences, WuhanDieter Meischner, Ingavat-Helmcke Rucha, and Helmcke Dietrich

Geottingen Center of Geosciences, University of Goettingen, Germany

AbstractA tentative correlation scheme for the tectono-stratigraphic units of Northern Thailand and those

of Western Yunnan (China) is proposed. We point out that a correlation between the Changning-Meng-lian belt in Western Yunnan and the Nan-Uttaradit zone in Northern Thailand (or and a “cryptic suture”in the Chiang Rai-Chiang Mai region) is unlikely, for it would demand a “suture” which cuts across a zonewith high-grade metamorphics and granite intrusions (Doi Inthanon-Lincang unit). Therefore, the northerncontinuation of the Lampang region is situated in the Simao region of Yunnan, as indicated by a verysimilar development during Permian and Triassic (Lampang-Yunxian unit). The Nan-Uttaradit zone isconsidered to be the easternmost part of this unit, and its northern continuation should be traceable viaLuang Prabang in Laos into the southeastern parts of the Simao basin. Here, however, outcrops of this unithave not yet been found. The same is the case with the Phetchabun unit which follows to the east. Bothunits are probably hidden under a thick cover of Mesozoic red beds. The whole region was characterizedby a highly mobile tectonic development with alternating phases of compressional and extensionaldeformation.

Published in Journal of China University of Geosciences, Vol. 12, No. 3, September 2001.

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THAILAND ENERGY DEMAND IN THE NEXT THREE DECADES

Kriangkrai Trisarn School of Geotechnology, Insititute of Engineering, Suranaree University of Technology

Abstract Before 1997, Thailand had been ranked one of the fastest-growing energy consumption in Asia,with an average yearly rate of 12% in the past ten years. The reason for such growth was the sheer volumeincreased in demand due to the rapidly expanding national economy at an average of 8-10% per annum.Since the fast economic growth collapsed in 1997, the total commercial energy consumption has beenstable as about 1.2 MMBOED , of this amount, oil products accounted for 54 %, natural gas 30 %, coal14 %, and hydroelectric power 2 %. Roughly 60% of consumption is being imported, mostly as crude oil ,and the rest as coal and electricity. It is believed that the growing prosperity should come back to Thailandagain. The GDP growth , as well as the energy demand, will be increasing in the next three decades. Theenergy consumption, which is estimated to increase yearly at 4%, 5%, 4%, 3%, 2%, and 1% during 2000-2005, 2006-2010, 2011-2015, 2016-2020, 2021-2025, and 2026-2030, will rise to 1.9 MMBOED in 2010,2.6 MMBOED in 2020, and 3 MMBOED in 2030 respectively. Someone might doubt how to get energysupply sources for these demands. The global oil production will rise to about 80 million BOPD in 2005and will peak at 90 million BOPD in 2010 and declined to an end in 2040.. The constrain in supplyingwill effect the price of oil, consequently create alternative energy sources such as phytoleum, syn.gasoline, shale oil, tar oil , coal petroleum, clean coal, nuclear, and renewable energy technologies. The natural gas, the environmental cleaner energy source, will be increased production in thecountry and as well as imported from neighboring countries will be added, LNG will be imported frommiddle east . Low sulfur coal will be imported to serve the demand. These supplies will be probably notsufficient until 2030, some new sources of energy such as synthetic gasoline, phytoleum, nuclear power ,more hydropower , clean coal , and some renewable fuels might join the list. The conservation andenvironmental awareness policy will also effect the energy consumption in the future.

ตีพิมพในการประชุมวิชาการดานเหมืองแร โลหะการ และปโตรเลียม ครั้งที่ 6 กรุงเทพ 24-26 ตุลาคม 2544

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GEOHYDROLOGICAL INTEGRITY OF STORAGE CAVERNS IN SALT FORMATIONS

Kittitep fuenkajornSchool of Geotechnology, Insititute of Engineering, Suranaree University of Technology

AbstractA concern for utilization of the underground space in rock salt has been the increase in its

permeability due to the inelastic dilation near the opening wall. For the waste isolation, the permeabilityincrease zone around salt excavations near the repository could provide a preferential flow path for thewaste to bypass the seals or plugs. For oil, gas, brine or compressed-air storage caverns, the permeabilityincrease zone induced by mining or by fluctuation of cavern pressures during operation may cause leakageto nearby caverns or to a high-permeability formation.

The objective of the present research paper is to predict the magnitude and extent of thepermeability increase zone (PIX) as a function of time, cavern shape, confining pressure (depth), andstorage (internal) pressure. Spherical, elliptical and cylindrical cavern models are simulated under avariety of confining and internal pressures. The results suggest that the characteristics of the PIZ aremainly governed by the initial in-situ stress (or cavern depth) and storage pressure. The in-situ stressesranging from 20 to 30 MPa (about 900 to 1300 m depth) result in the largest PIZ of nearly twice thecavern radius. The permeabilities increase with time and reach their ultimate values within one year afterexcavation. These ultimate permeabilities are largest near the cavern boundary, and could be severalorders of magnitude above the in-situ value. Raising the storage pressure can effectively reduce themagnitude and extent of the PIZ. Salt permeabilities around the cavern with a large diameter-to-heightratio may be several orders of magnitude greater than those around the spherical cavern. Care should betaken in applying these approaches and results to an actual group or array of storage caverns. Influencefrom the nearby caverns including their age, mining sequence, past and current storage pressures, size,shape and spacing must be considered for the determination of the PIZ.

Published in the Symposium on Mineral, Energy, and Water Resources of Thailand, ChulalongkornUniversity, Bangkok, 2000.

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ALIGNED FRACTURES IN CARBONATE ROCKS: LABORATORY AND IN SITUMEASUREMENTS OF SEISMIC ANISOTROPY

S. Dey-Barsukov, W. Rabbel, and S. WendeInstitut für Geowissenschaften, University of Kiel, Germany

H. Dürrast and S. SiegesmundInstitut für Geologie und Dynamik der Lithosphäre, University of Göttingen, Germany

AbstractBy vertical seismic profiling and shear wave analysis we show that a packet of carbonate

reservoir rocks, found at nearly 3000 m depth in the North German Basin, is seismically anisotropic. Forvertical paths of wave propagation the estimated velocity difference of the split shear waves is 10%. Noshear wave birefrigence is observed within the hangingwall which, therefore, has to be regarded asisotropic or transversely isotropic. Additional laboratory investigations of the petrography of drilledcarbonate samples and of their seismic velocities show that the anisotropy is most probably caused bysubvertical fractures with preferred azimuthal orientation. The strike direction of the aligned fracturesdetermined by analysis of split shear waves is approximately N55°E. This value agrees with recentlypublished directions of maximum horizontal tectonic stress in pre-Zechstein sediments in the eastern partof the North German Basin, but it is in contrast to the world stress map.

Published in International Journal of Earth Sciences, 88, 2000.

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PERMIAN FACIES OF NORTHERN AND NORTHEASTERN THAIALND: IMPLICATIONFOR GEOTECTONIC EVOLUTION


AbstractThe Permian sediments are distributed extensively in every parts of Thailand. They were

popularly known as the Ratburi Limestone whose type area is in the Ratchabiru province, westernThailand. Subsequent works in northern and northeastern Thailand led Bunopas (1981) to doubt theequality of these limestone units. He proposed the names Ngao and Saraburi Groups for the Permianlimestones in northern and northeastern Thailand respectively. It is now widely accepted that the RatburiLimestone, based on its fusuline contents, is quite different from the comparable limestones in the northand northeast. The former belongs to the peri-Gondwana realm, whereas the latter two belong to theTethyan realm. Although the Permian carbonates in northern and northeastern Thailand are similar in termof its funnal contents. They lithofacies are different as they were deposited in different tectonic settings.

ตีพิมพในการประชุมวิชาการเรื่อง ธรณีวิทยาและแหลงแรประเทศไทย 20-21 ธันวาคม 2543

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CORRELATION BETWEEN ROCK FABRICS AND PHYSICAL PROPERTIES OFCARBONATE RESERVOIR ROCKS

H. Dürrast and S. SiegesmundInstitute of Geology and Dynamics of the Lithosphere, Georg-August-University of Göttingen, Germany

AbstractThree carbonate core samples from an oil and gas reservoir of the NW German basin were chosen

to study the correlation between rock fabrics and physical properties of reservoir rocks. Detailed fabricanalyses and texture investigations were carried out as well as laboratory measurements of differentphysical properties, e.g. density, porosity, permeability, electrical conductivity, seismic compressional andshear wave velocities. Although the three core samples come from a similar depositional facies, they showgreat differences in the occurrence and three-dimensional distribution of the rock fabric elements. Theseheterogeneities are the result of various diagenetic and tectonic processes. For the correlation between therock fabrics and the physical properties four main rock fabric types have to be considered: (a) majorconstituents, e.g. fossils, ooides, peloides and crystals; (b) pore space with different pore types; (c)fractures; and (d) stylolites. The results of the correlation clearly show that the values and anisotropies ofthe petrophysical properties are fairly related to the observed fabric elements, with their differentarrangements, spatial distributions and preferred orientations. These results also provide a fundamentalunderstanding of the petrophysical responses, such as seismics, to the different geological features (e.g.fractures) and their dynamic changes with pressure, which can be converted to different depths. Theknowledge gained from such correlation may lead to an improved interpretation of geophysical data forhydrocarbon exploration and production and therefore to an advanced reservoir characterization.

Published in International Journal of Earth Sciences, 88, 1999.

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GEODYNAMIC EVOLUTION OF LOEI AREA-NORTHEASTERN THAILAND


Dietrich HelmckeInstitute of Geology and Dynamics of the Lithosphere, University of Goettingen, Germany

AbstractBased on the discovery of detrital chromian spinel in sandstones of the Permian Nam Duk

Formation Chutakositkanon et al. (1997, 1999) suggest a new suture and terrane boundary in north-centralThailand which they named “Loei Suture” and which they trace from north of Loei through Phetchabun tothe region of Saraburi (Chutakositkanon et al. 1999, Fig.5).

We fully recognize the importance of the discovery of the chromian spinel detritus in sandstonesof the Nam Duk Formation since it confirms the interpretation that the siliciclastic part of the Nam DukFormation is related to an evolving mountain belt caused by contractional deformation during late Middleto Late Permian times (Helmcke & Kraikhong, 1982). But we disagree with the interpretation that theinflux of the chromian spinel is due to the closure of a previously unknown suture which runs from theP.R. of Laos via Loei in northeastern Thailand to the south. We still favour the view that the evolutionrecorded in the sediments of the Nam Duk Formation reflects the closure of the Nan-Uttaradit Suture(Chonglakmani, 1998, Helmcke & Lindenberg, 1983). To substantiate our point of view we like toreiterate and to reevaluate some previously published information by various authors.

From Chiang Khan on the Mekong River to Wang Saphung south of Loei an apprarentlyimportant tectonic line can be drawn which marks the western boundary of the region tentativelydescribed by Workman (1975) as a Hercynian Massif. Based on fossil finds by Fontaine et al. (1981) andhis own data, Altermann et al. (1983) suggestes that the main deformation in this region can be datedapproximately at the Devonian/Carboniferous boundary. The Carboniferous and Permian strata are clearlymuch less deformed. The description of the Loei area by Chairangsee et al. (1990) does not highlight thestratigraphic age of this main orogenic event.

But the data on the basement of the Khorat Basin (Kozar et al., 1992) prove that the basindeveloped in a region affected by an Early Carboniferous Variscan event, which is manifested in anangular unconformity. The Variscan Unconformity divides the Loei Group from the Saraburi Group(Mouret, 1994). Strata of the Saraburi Group are distributed in most parts of the Khorat Basin proving that

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the likely southern continuations of the Loei ocean floor tholeiites and the Loei rhyolites dated by Intasopa& Dunn (1994) could not have been eroded during Permian times.

Orogenic activity of this range in age (mainly Early Carboniferous) is well known from regions inVietnam (Fontaine & Workman, 1978) and the ages reported by Intasopa & Dunn (1994) for the Loeiocean floor tholeiites and the Loei rhyolites are not in conflict with the given interpretation. The agesrecorded in detrital muscovites of the Khorat red beds mentioned by Heggemann (1994) support Devonianto Carboniferous orogenic activity.

On the contrary to the above mentioned region. The Permian strata of the Nam Duk Formationalong the Lom Sak-Chum Phae highway which contain the detrital chromian spinels recently reported byChutakositkanon et al. (1997, 1999), are severely affected by contractional deformation. This deformationwas first dated by Chonglakmani & Sattayarak (1978). They discovered a pronounced angularunconformity between deformed Permian Nam Duk Formation and the Upper Triassic Huai Hin LatFormation approximately at km 34 of the above mentioned highway (Chonglakmani & Sattayarak, 1978,Fig. 15). In the following years the stratigraphy and facies of the Nam Duk Formation were studied. Theyoungest deformed fossiliferous strata found were dated by H.G. Lindenberg (Fig. 16, 17 in Helmcke &Kraikhong, 1982) and by R. Ingavat (Fig.4 in Altermann et al., 1983) as Murgabian and very likely alsopart of Midian. These data are now independently confirmed by Chutakositkanon et al. (1997, 1999).Based on these data, the main orogenic event which affected this region has been dated as approximatelylate Middle Permian-early Late Permian. Only some K-Ar age determinations on the fine mineral fractions(Ahrendt et al. 1993) support this interpretation. The younger ages found are probably caused by youngerthermal overprint or the respectively younger intracontinental deformation. The pronounced angularunconformity (Chonglakmani & Sattayarak, 1978) between the folded Permian strata and the UpperTriassic sediments cannot be overlooked.

Paleocurrent indicators recorded in the siliciclastics are deposited by turbidites and point to asediment transport parallel to the axis of the basin and gave therefore no conclusive result where to expectthe source area. If we discuss the possibility that the source area of the siliciclasitcs deposited by turbiditycurrents of the Nam Duk Formation was to the east as some authors suggested, we have to correlate thestratigraphic column of the Nam Duk strata very carefully and in more detail. Mouret (1994) may serve asan example. He suggests that the sudden sand influx in the Nam Duk Formation is caused by a majorrelative sea level fall which occurred according to the data by Dawson et al. (1993) during the Bolorian.This possible explanation cannot be substantiated by stratigraphic results obtained in the Nam Duk

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Formatoin because they indicate that the sudden influx of siliciclastics started not earlier than the lateKubergandian-Murghabian (R. Ingavat in Winkel et al., 1983, Fig.2).

However, the distribution of the Nan-Uttaradit ophiolite and the geometry of the folds exposed inthe Nam Duk strata suggest that the subduction zone was located to the west. Therefore we expect thesource area of the newly discovered chromian spinel detritus in the more internal zones of the risingmountain belt farther to the west. We regard the areas to the east of the section along the highway LomSak-Chum Phae as foreland areas and the possibility of major influx of detrital material during the lateMiddle Permian from the foreland area seems to us quite unlikely.

If we accept the data by Intasopa & Dunn (1994) indicating a Loei ocean, this ocean was alreadyclosed in pre-Permian times. If the Loei suture has a continuatoin to the south, then this continuation mustbe searched for in the deformed basement of the Khorat Plateau. The occurrence of the Paripteris flora(Laveine et al., 1993) in the Loei area witnesses that this region was already fully integrated into theNorhtern Continents in the Late Carboniferous time.

According to the data mentioned above we cannot accept the interpretation of the “Loei suture”(exposed in the mountains east of Loei, Intasopa & Dunn, 1994) as an important tectonic divide that runsfrom the Mekong river via Loei towards south into the Phetchabun region. The geodynamic evolution ofthe Phetchabun region is by all means incompatible with the situation depicted in the area east of Loei.

Published in Geodynamic and Tectonic Evolution of China and Related Gondwana Crustai Fragments,1999.

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STRUCTURAL DAMAGE EVALUATION OF NATURAL BUILDING STONES:POTENTIAL AND LIMITATIONS OF ULTRASONIC DIAGNOSIS

H. DürrastInstitut für Geologie und Dynamik der Lithosphäre, Georg-August-University Göttingen, Germany

S. SiegesmundGeologisch-Paläontologisches Institut, University of Basel

M. PrasadGeophysics Department, Stanford University, Stanford, CA, U.S.A.

AbstractRecently, ultrasonic measurements are gaining importance as non-destructive tools for evaluating

structural damage on historical landmark buildings and artworks. In these methods, P-wave velocity (VP)measurements are correlated with porosity increase due to fabric damages in the stone. Such correlationprovide us with a method of measuring of the degree of structural damage due to erosion using indirectmeasurements. Damage prevention and repair planning are made on the basis of such a VP-structuraldamage classification. A major advantage of this technique lies in its non-destructive nature. We havetested the existing VP-structural damage classification system using three dolomitic samples withporosities ranging between 5 and 16 %. The samples were chosen as analogy to marble, which is one ofthe most important natural building stones. These measurements were used to evaluate the VP-structuraldamage classification system for marble and to compare the VP-structural damage classification withexisting VP-porosity models. Detailed petrographic and fabric analyses as well as petrophysicalmeasurements such as density ( ρ ), porosity (Φ ), and the complete VP-distribution were made. Usingthese detailed measurements, we could correlate the VP-anisotropy with the anisotropy of the rock fabricelements in each sample.A comparison between our measurements and existing VP-Φ models shows that a decrease in velocitycannot be explained only on the basis of porosity increase, without accounting for the change in the rockfabric due to erosion. Our studies show that the currently used simple VP-Φ transforms and the associateddamage classifications need to be improved to include fabric and mineralogical changes which oftenaccompany structural damage.

Published in Z. dt. geol. Ges., 150/2, 1999 (in German, with English abstract).

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WHAT SHOULD BE THE ALTERNATIVE ENERGY MIX SUPPLY FOR THAILANDIN THE NEXT THREE DECADES?

Kriangkrai TrisarnSchool of Geotechnology, Institute of Engineering, Suranaree University of Technology

Visarut TungsoonthornkhunDepartment of Mineral Resources

AbstractThailand has been ranked one of the fastest-growing energy consumption in Asia, with an average

rate of 12% in the past ten years. The reason for such growth is the sheer volume increased in commercialenergy consumption now is about 1.1 MMBOED, of this amount, oil products accounted for 62%, naturalgas 22%, coal 13%, and hydroelectric power 3%. Roughly 60% of consumption is being imported, mostlyas crude oil, and the rest as coal and electricity. The energy demand, which is estimated to increase at 9%,7%, 5%, 4%, 3%, and 2% in the next six five-years intervals, will rise to 2.8 MMBOED in 2010, and 4.4MMBOED in 2025, someone might doubt this energy mix supply will last until 2025. The global oilproduction will rise to about 80 million BOPD in 2005 and will peak at 90 million BOPD in 2010 anddeclined to an end in 2040. It also projects that OPEC’s role in supplying demand will simultaneouslygrow to over 50% of output beyond 2005. The constrain in supplying will effect the price of oil,consequently create alternative energy sources such as shale oil, tar oil, coal petroleum, clean coal,nuclear, and renewable energy technologies.

The natural gas, the environmental cleaner energy source, will be imported from neighboringcountries, LNG will be imported from middle east. Low sulfur coal will be imported to serve the demand.These supplies will be probably not sufficient until 2025, some new sources of energy such as nuclearpower, more hydropower, clean coal, and some renewable fuels might join the list. The conservation andenvironmental awareness policy will also effect the alternative energy mix supply in the future.

Published in the International Conference on Stratigraphy and Tectonic Evolution of Southeast Asia andthe South Pacific Bangkok, August 1997.

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ENVIRONMENT AND SAFETY CONCERNS IN PETROLEUM INDUSTRY IN THAILAND

Kriangkrai TrisarnMineral Fuels Division, Department of Mineral Resources

AbstractDevelopment of new energy sources, exploration as well as production, distribution,

transportation and consumption, all have the capacity to create Seven environmental impact.The research for petroleum in Thailand began in 1921 by the Department of Royal State Railway.

Many exploration efforts were continued by the Department of Mineral Resources, but no significantdiscovery was made, except the Fang basin. The new era for petroleum development began in 1962, whenThailand changed her strategy to invite experienced oil companies world wide for challenging the risk.Moreover, the Petroleum Act and Petroleum Income Tax Act were first promulgated to administer thePetroleum E&P in 1971. The petroleum productions now (1996) consist of 1,100 MMSCFD of gas 31,000BPD of condensate and 25,000 BPD of crude and accounted for 260,000 BOED or about 30% ofconsumption.

-The significant transportation and marketing of petroleum products was started in 1892, " Crow "kerosene by SHELL group. In 1894 Standard oil company of New York (Esso) established its branch inThailand. Thailand's first refinery was set up in 1940, by the Fuels Department, Ministry their refiningoperation in 1964. Esso purchased a plant from Thai Asphalt Company and started refining operation in1967. SHELL and Caltex, two new refineries started the operation in late 1996, added up the totalThailand refining capacity to 750,000 BPD.

Petroleum exploration and production is operated under the Petroleum Act under the supervisionof the Department of Mineral Resources. The success of petroleum development in Thailand has primarycome from concessionaries found as Thailand's petroleum potential remains ample.

Many acts such as Factory Act, The Investment Promotion Act, Public Health Act, DangerousSubstance Act, Land and Transportation Act, Labor Act and international standards such as InternationalOil and Petro-Chemical Safety Rating System (ISRS), American Burean of Shipping (IBS), AmericanPetroleum Institute (API), International Standarization Organization (ISO), and Environment Policy(HSE) require compliance for petroleum industries. One-Stop-Service-Center is the main key to promoteactivities.

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The Department of Mineral Resource's policy is to maximize the exploration of resources to theutmost efficiency and benefit, and at the same time minimize the impacts on environment. There arecurrently no laws or regulations that deal specifically with environment management of upstreamhydrocarbon industry. However, in practice the provisions of the Petroleum Act 1971 is applicable to thepetroleum operations of the concessionaries in all stages of operations. The results are somewhatsatisfactory. It is anticipated that laws and regulations to deal specifically with environmental managementof upstream hydrocarbon industry will be issued soon.

Published in CCOP/ASCOPE/PETRAD, Environment and Safety (CAPES), Pattaya, January 10-12,1996.

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PETROLEUM AND ENERGY SITUATION FOR INDUSTRIAL DEVELOPMENT INTHAILAND AND INDOCHINA

Kriangkrai TrisanMineral Fuels Division, Department of Mineral Resources

AbstractIndochina is considered to be one of the most important economic regions in the world, where

Thailand and Vietnam both have the GDP (Gross Domestic Product) growth of 8-9% while Cambodia's and Lao's are at 5-6%per annum. Petroleum activities contribute an important value to the total GDP of Thailand and Vietnam. Petroleum and other energy sources play an important role in the industrial development of the region. The more the industrial development expands, the more the necessity in managing energy supplies increases. Thailand and Vietnam have their significant petroleum reserves while Laos and Cambodia have their high potential hydropower. The interchange of energy supplies and trade cooperation will accelerate the industrial development in this region.

Published in the International Conference on Geology and Mineral Resources of Indochina (Geo-Indo'95), Khon Kaen, November 22-25, 1995.

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