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OEOLCTjICAL Aft) KAGNBTOHETKR SURVEXS

ON THE

NSST-BEMBOFi GROUP OF CLAIMS

XENOCAMINQ TOWlfiHir

PROVIDE OF ONTARIO.

by

R. Seavoy,

- Exploration Pivisioin - Canadian Johna-l'cnville Co. Limited. [

February ^th, 1957, Watheson, Ontario.

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43Ae4NWai67 63.826 KENOGAMING 010C

TABLS OF C'ffTEOTS

Location •....••••••....,

Accessibility ................,

History ............,....,

Topocrtipty ..........,.,.....,

Regional (ieolopy .......... .*......,,

J'etailofl Geology .....*.........,,...,Stratlp.raplny

Strtioturua ...................,

Geophysicul Corr. ........ ..i........

Economics ........ *.......i.

Conclusions ...... .....*.....

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2. 3

3* 4

4, 5

55, 66

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Geologic anrl Topographic Flan

I'agnetomoter Contour Flan

l" * 200 1

l" - 200'

NBST-BENBOW LAKES CffiOUP

loo* t i on

The Nest-Benbow claim group IB located in the northwest corner of Kenogaming township, northern Ontario. The we B tarn boundary of the group extends into Pen horwood Township. The southern boundary of the group is the north shore of Hanrahan Lake while the eastern boundary it formed by the portage trail connect ing Hanrahan Lake and Benbow Lake. The north boundary of the group is an approximately eaet-west line about half a mile north of the ?J mile post on the Kenogaming-Penhorwood Township line*

AocesB

Access to the property was by airplane which landed at the old lino cutter oamp, on a point of land just opposite the big island at the north ond of tho lake. Because of very shallow water at the far north ond of the lake, all supplies were transferred from the plane tt a canoe, which was brought along, a nd then ferried to the camp site*

History

This group consists of 16 full claims and portions of several others. It was staked in February 1955 along the strike continuation of the north line of tho Montgomery Lake iron formation; which ve know to bo massively mineralised with barren sulfides,

Prior to J. M. 'e staking, the banded iron formation had boon intensively pros pected for base metals and gold. The iron formation has many pods and lenses of syngenetic pyrite which have been trenched, Vhere hydrothermal pyrrhotite wae found, a prospect shaft, probably JO or ^0 feet deep, was found. Prospecting in this area, on this formation was probably aoat intense, just after World Var Z. The first Ontario De pt. of Mines bulletin Ox this area, published in the 1920* s records the single outcrop of Iron formation! north of the regional iron forma tion; the one on which the prospect shaft Is located. The only reason this out crop could be known was that at that time, work had recently been done on it*

During the summer of 1956 lines were cut across the property. The lines were out at right angles to a baseline which strikes H ?0 X. In the fall of 1956 Ronald E. Seavoy ma ped the geology while lawrence Allleon completed a ground magnetometer survey. In January of 1957 this information was compiled and this report submitted.

The south end of the claim group is tha north end of Hanrahan Lake. The west shore of Hanrahan Lake, where it is included in the claims, is a low, flat- crowned ridge of green boulder clay. It is cohered with a senile growth of white birch and balsam, which has for the most part died, creating a jumble of wind- fallen logs. The ground cover is made up of douse growths of moose maple, red- twig dogwood, hazel nuts, balsam, spruce and birch suppling*. The only mature

trees standing are eprue©, Jack pin© and the reminder of the Rupture white birch.

The whole north boundary of U* property ie a high sand ridge; nicest ia the vest and flattening to the east. It be&ine ii*i0diately north of Neet Lake and ex tends north off of the boundary of this prospect. Kettle Moraines are very prom inent to the went. This r id,', -e ie covered with m ture stands of yellow pint and extensive groves of ec^ui-a^ed ix)plar. The forest floors of theee timber types are open while the mixed forest areae nave euoh under brueh. The nixed f ore e t if found in th© shallow but nteep, valley e between the dunoe-oap-like kettle norainea where there IB a hif*her fraction of cluy ttitierale in the eoil.

centre portion of the (troup, following the two lakes and connecting stream ie very low and ewtuupy, Extensive swnrape and apruoe f l r te surround Meet Lake, es pecially to th* went earl nouth. U'heee isaac open, pork-like spruce flats are found at the northwest corner of Hn&r&hra Lake.

Fhft enatern cent rf il i* r t of th^ Rroup, near the end of the baeeline and along the eoutli ehoro of Benbow Ltik^ ie e rid^, gain Inf. hei^t to tht eaet where it drope off quickly into ewparp l'?n and Benbow L"kei This eo^rp if composed of banded iron foliation and IR ;pf roxirvotcly parallel to t)M bneeliae. The swamp •jonbol on tiii r, IE-IP repreoente open, boc Iwad, devoid of any under brush or trees.

Putcrope in thic wliole area are relatively scarce and what outcrops occur, are in groups along the creetp of ridgee or BAjirpe* Sven then, the outcrops are not large. The noet conspicuous rock r*nd mont consistently outcropping rook ie the banded iron fom tion. H cm be followed for miles, either in its continuity, or

•r ia broken ee^itntc - l, by ground tna^ne tome ter survey, Z - projection, along strike, Of outcrops. Tiie banded iron lo na lion was apparently aost reoictent to glaciation. l do not thinic it n&k&e up Bore than a fraction of the rook in the region*

Probably the laost ooiwiion rock type in |he area ie the basic to intermediate volcan le c, alont; with vrtrying proportions |f inter-bedded sediments. These do not resist erosion, fh* next tuoet oouwon rook after the volcanics is probably granite, but not as large area pluton e. the granites are more erosion re si s ten t than the•edinents~voloanicB but still are not conspicuous. ?he asxt most oowion rook is probably the basic iiitrueivee (gabbro-diorite) rAe extent of this rook type in any area 00 heavily toantled with overburden, is a guess.

Strike faults are the most common recognisable structural feature. These are extensive and of large dinensione. Folds fcrt very difficult to define, beoauee*ost, if not all, dipt! turn vertical or ne-* vertical. Only where the iron forma tion sake e a grent flexure can a fold be detected and then we are ia doubt whether It is w* anticline or syncline.

ffo the west, the granitos rnd ^bbro*dioritee occur as very snail dikes to large plu^ up to several clnirt in feres. This was ®ieo true of the serpentines.

Regional r.e t r* mor ph i Bm in more evident in this area than in the nurroundlng region. Ga met R were found in the iron f enation and the shales are changed to ohlorite-actinolite ^ni t le schists. f^i4 basic volcanics exposed in the north west of this elrltt bloc were not profoundly chan-ed, however, they were hydro-

(3)

thermaljil)Aaltered to a carbonate rich rook, f wad i he south east part of the claim bloc, to be regional.

This was also true to the gabbro This carbonate alteration stems

Detailed Otology

I Stratigraphy

The eld*Bt rook unit, is the series ef basic to intermediate TOleanlos; pro bably submarine flows. They have been altered and metautrphited mere than usual for this region, Metamorphism has obliterated all structure and hydrothermal solutions have altered it to rook rich in carbonates, mostly in snail gnash reins and fractures.

On top of the volcanics was laid a series ef fins grained elastic sedimentsj some ef which had magnesium in them, probably in the fora ef dolomite. These sediments have been altered to ohloritt-aotinolitt and talc schists* Vhtrt thsrs is any appreciable amount of actinolite, there is usually an appreciable content ef magnetite. The magnetite is probably of detrital origin. There is little ojiartit. with the chlorite schists so they erode easily. They weather white and have been extensively intruded by granite dikes, parallel to the strike of the banded iron formation.

The most conspicuous rock unit is the baided iron formation. It has been traced completely aoresB the area by ground magnetometer survey. This has been correlated by the surface geologic survey. It extend! unbroken to the east, along the south shore of Benbow Lake, Wherever bedding wa* observed, which was often, the forma tion was vertical or near vertical. The highly magnetic strata is consistently about 200 feet thick, thinning slightly to the west. However there are portions which are not so magnetic, in fact, they nay be the opposite, but the appearance is the tame. This similar looking strata, noa-a*gnetio, however, increases the aver age width of the iron formation to about 350 "* 4^0 feet. Again the width seems to diminish to the west.

The banded iron formation consists of alternate bands of silica sand and det rital magnetite or scaly limonite-hematlte* The silica sand is often pure and whits it is well sorted and the grains are frosted, The sand makes up about 80^ of the formation in the most magnetic and pyritifefous strata, and almost 100^ in other parts. This accounts for the great magnetic variation within this recognisable unit.

Vi thin the banded iron formation, particularly in the silica sand-shaly limonite portions, there are often short flat lenses or pods tf syngenetic pyrite, with well formed cubes. These sulfieds, since they Art coarse, weather easily and much Attrital magnetite is also released. It is this portion of the iron formation that WAS intensely prospected,in the past, and ttenched.

There is also a euxinic facies in the batted iron formation. This faoios it fine grained, the pyrite being found as nodulis in a denss black, siliceous slates. With the black slates are fine bands of greenish black chert and a very fine grained greenish sandstone; alternating with thin Mads of detrital magnetite. The magnetite Itnsts are sulfide-free. This fine grained chemically deposited facies is found hear the top of the iron formation. It is Richest in magnetite and has a very regular contact with the overlying fine grainsd green quartzite.

Stratigraphicly above the tended Iron formation, to the south* IB a thick and cons IB ton t bed of a very fine grained groen, dense quar t site, with very fine bedding composed of biotite flakes. In every outcrop, the dip was vortical or noar vortical, thus conforming with the banded iron formation, f his formation consistently averaged 600 to ?00 feet in thickness. It it very hard and weathers whitish. On a fresh outcrop that has been exposed for a long tine, the fine bio tite bedding gives this formation the appearance and texture of a fine grained gneiss, and the uniform color suggests rhyolite* However, it is very dark, too consistent along strike, and gritty for a rhyolite. The grain sire is so small it is almost a chert. I'he grain size is best seen on a weathered surface* The Biotite bedding is not nuoh more than one mica scale thick and the rook is proa- ably 9# silica.

The next rook typo is the basic intrusiTes, All of them were grouped to gether except for the diabase. Outcrops were United but those found woro altered especially by carbonation. This makes correlation very likely with the gatbro- dierfcte series of Jeharm South Extension, One diorite outcrop was coarsely crystalline and doeply weathered. It nay correlate with 6A, the lato coarse grain diorite, found in the Jehann South Extension.

The next rook unit is granite. Host of the granite outcrops were as dikes in the sediments. Only in one place were outcrops consistent enough to warrant call ing any area granitic* And here, because of the siliceous nature of the enclosing reek (probably sedimentary schists) it is very difficult to outline the pluton, therefor, it was left indefinite. This granite is fount near the iron formation having hydrothermal pyrrhotite in veins and nay be the source of the pyrrhotite.

She next rook unit is serpentine* There were* no large magnetic highs suggest ing ultra-basic intrusives; however, there were a number of very small ones* These line up along the inferred inner contact of the green quart tite* This seems a likely place for their emplacement, light green, slightly carbonated serpentine drift was found in several places. There was no fiber in any chunk. In view of the ground magnetometer results, it appears unlikely that there is serpentine in any quantity on thie prospect.

The last rock type observed was diabase. It is intruded in dikes that seem to conform to the regional strike instead of cross-cutting it. Evidence for this Is a large east-west striking outcrop that fes a porphyritic phase along its north face. This would be difficult to explain if the dike were striking north-south,

II Struqtxyes

The most prominent structures on thie prospect are two small isolated areas f high magnetic intensity, north of the regional iron formation. I have inter preted these ae doubly plunging synclinal troughs, the very bottom being all that remains. From this interpretation I have inferred that the top of the regional iron formation is to the north. On the large* t of these Magnetic highs, the upper "iron formation", there is one outcrop, TUB is along the margin of the high. The *utorop consists of a highly sheared, dtfk green quartette, veined with aass- ive pyrrhotite up to 6 inches wide. There it t prospect shaft sunk on this out crop. This green quar t si to could be the formation above the regional iron forma tion, but it is too badly sheared to tell. JBeOftse of the lack of more outcrops, we must conclude that this rook type could bs ajgrwhere in the sedimentary series.'

( 5)To ̂ . vest are two parallel iron formations, perhaps these are faulted rem nants oWzenoliths preserved in enclosing granite. In the original reconnaissance through this area, in the early l920's, and published by the Ontario Bureau of Mines, this one outcrop was noted and labeled as iron formation, l accept this designation because he probably saw fresh rook from the prospect shaft; however, this iron formation remnant is probably highly altered, In order to find this outcrop the reconnaissance mapper must have come through when the prospect shaft was being sunk or soon after, when there still was interest in the area*There also exists the possibility that the magnetite is of hydrothermal origin and ia an accessory to the pyrrhotite that is found in the highly sheared rook, In the regional banded iron formation no pyrrhotite was found, so it is assumed that this pyrrhotite is of hydrothermal origin.

The upper and larger remnant of "iron formation" has a distinct displacement* This is interpreted as a fault* The fault is assumed to continue south, termina ting the smaller "iron formation" remnant and cutting the regional iron formation In the regional iron formation there is little evidence of displacement or fault ing* However, to the south, and on strike with the direction tf apparent dis- pladement of the upper "iron formation", there was observed some very large barron boulders of white quartz. This is assumed to be the trace of the same fault AS displaces the upper "iron formation".

Further faulting is difficult or impossible to detect, either from aerial photos, magnetometer survey, and geologic turvty, and fr"om correlation of all three there is the possibility of a large etrik* fault directly to the north of the regional iron formation. Evidence for this is the closeness of volcanics to the regional formation at the west end of the claim bloc and the presence of sediments in the same relative position further east. ^e lowlands and connecting stream of Vest Bonbow Lakes would follow this fault and the upper "iron formation" rem nant e would become down-faulted remnants and not folds.

Ill Geophysical Correlation

the lack of outcrops throughout the area very much hindered correlation of the ground magnetometer survey with rock type i and major structures. The ground magnetometer survey has been the only ground geophysical survey run so far.There are some north-south trending 10*40* tic lows of large dimensions; but it is unsafe to call these granites because tat sediments beneath the regional iron formation are siliceous and rich in carbonate or carbonate rich minerals. Besides the known granite outcrops are not on lows. Thus I have left large areas blank.

IV loenomiceNo inferred serpentine body of any si st exists and thai this area it of little interest in the search for fiber but the are* does have definite interest for base metals exploration*

f he upper "iron formation" has no outcrop to define it ft* an iron formation It is of very limited extent being 1200 felt long and 4-50 feet wide ait its widest. Its magnetic intensity is very high and iti area very closely defined by surround ing lows. A prospect shafjb has been sunk to the edge of this high where some thin stringer veins of pyrrhotite are found in an intensely sheared quarteite, A grab sample of this pyrrhotite assayed l?l gold per ton and nil in copper, nickel silver and cobalt*

It ir poseible that the hi{jh magnetic intensity of thi* closely defined area could be due to hydrothermal magnetite aocwpanying further and nore extensive sulphide mineralisation. Since the prospect ahaft vat tank en an outcrop at the Tery edge of the magnetic anomaly, it alone doee not tell what is there* fhat happens to be the only outcrop (or the only ene found by the author), on this anomaly.

Although the regional iron formation contain* sulfideBy they are of syngenetic Origin and only of momentary interestJ

ponelusions

The claim fcloc wae not large enough and/or there was not enough rock exposed to draw in or postulate) any regional structures beyond the obvious, fchis means that the very largest regional structure e, only, were drawn in (regional iron formation) and only the rock types near outcrops could be psotulated. Beyond this the area is best left blank because it is not known how the magnetic mediums and lows behave in relation to the rook types in the surrounding region* However, our interest in the highs is well served by the map as it stands.

Recommendations.

fhis claim bloc has no further interest for asbestos fiber exploration. Neither does the regional iron formation hold any further interest in base metal exploration unless something of interest is found in the upper "iron formation11 . In that event, furhter attention to the regional iron formation would be in J.H 1 s interest.

It would, however, be in J.H.'s immediate interest to make a reconnaissance Bf survey over the upper"iron formation" remnants and also a detailed magnetometer survey, to find out Just what might be present* Such a limited area with so many signs of mineralization, with so little information, is of definite interest.

The saw mill on Akweska Lake is planning to build an all weather road into the east shore of Hanrahan Lake next summer* Therefor, J.M.'s interest in this area should be current, so that if further interest in this area dees develop, due to further exploration, then J.H. can be prepared, next winter to go in, put down a hole and get out again, quickly, if nothing develops.

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' ' -' KEST-BEHBOW LAKES G30UP

location

Tha Hest-Bsnbow c In in sronp is located in the northeast corner of Keno,2aning Northern Ontario. 5?hs western boundary of tha group extends into Pen

horwood Tov/nchip, Th'j southern "bci.uadp.ry of tha group is the north chore cf Eanranxn Lake while ths easisra boundary is forced by tha portage trail connect ing Eanrahan Lake and Bsnbo^f Laka* 2hs north boundary of tha group i s aa approximately east-wast line about half a nile north of ths 7^- Bile post on tho Xesogaains-Penhorvood Tov/nship Iic3.

Access

Access to tha property was by airplane which landed at ths old line cutter camp, on s. point of land Juct opposite tho big inland at tba north end of the lake. Bacaursa of vary shallow water at the far north end of tba lcbs f all supplies were transferred fron the plane to a canoe, v/hlch was brought along, a nd then ferried to ths camp site*

History

This group consists of 16 full claims and portions of several othera. It vas staked in February 1955 along tha strike continuation of tha north lina of the Montgonsry Like iron formation; which we know to be Eiassivsly mineralized with barron sulfide a,

Prior to J. M. 's staking, the banded iron forioation had bosn intensively pros pected for basa cetals and gold. The iron formation his naiiy poda aud lenses of syngenetic pyrite which have been trenchad. Whsre hydrothermal pyrrhctita was found, a prospect shaft, probably 30 or ^0 feet dsep, was found. Prospecting in this area, on this formation was probably most intense, just after 'Jo r Id Vor I. Tha first Ontario Dspt. cf Mines bulletin ea this area, published in the 1920* e records ths ein^lo outcrop of Iron formation, north of tha regional iron forma tion; the one on which tha prospect shaft is located. 5?h5 onlj' reacon this out- . crop could be knovra waa that at that tiLis, work had recently been doiae ea i t,

During the summer of 195^ lines were cut across tha property. Th? lines were cut at ri^t angles to a baseline which strikes H 70 2. In ths fall of 1956 Ronald E. Seavcy ea, pod the geolo^ while Lav/rence Allison conplcted a grcxmd iaagnetGn9t3r survey. In January of 1957 this information '.-;a.s compiled and this report submitted.

She south end of the claira group i a the north end of Kanrahin Lake. vest shore of Hanrah.an Lrdca, where it is included in tha clains, is a low, flat- crovmo-i ridga of green bouldsr clay. It is covered with a senile growth of white birch and balsia, which has for ths moat part died, creating a Juable of v/iiid- fallen lo^s. Tha ground cover is c?.de up of dsnse growths of noosa napl-a, red- twig dogwood, hazol nuts, balsas, sprue a and birch sipplings. I'ha only u-xture

(2 )

reas standing ore spruce, jack pine ead tba recainder of the isature white birch.

!?he whole north boundary of the property is a high Band rid^o; highest in tho veat end flattening; to tha east. It bagins immediately north of llest lake end ex tends north off of the boundary of this prospect. Kettle moraines ara very proa- inent to tha waot* This rid^-e is covered with B- turo atanda of yellow pine and extensive grovaa of equi-a^ed poplar. The foroot f looro of these tinber typao oro open vhile the isized forest areas have nuch -under brush. Tho snixed format if found in the ehalloa but starjp, v&lloyo between tho dunce-cap-like kattle aorainaa where there is a hi&nar fraction of cl?'y minerals in tha soil.

The centre portion of tha group, following the two Inkoo end connecting etrsrja is very low and ewniaty. Ivxtansive ouasipg end opmce fl-^-te surround lieat Lalas, es pecially to tha vest ani south. Thaso sane open, park-like spruce flats era found at the northwest corner of Ifanmhan Lake.

The eastern central part of th* croup, near the esvl of tha basslina and the south shoro of }Jenbow Lelcft is R ridi~j, gaining holtht to the cast where it drops off quickly into evrjnp l^n ! and 3enbow L"ks9 This ec ^rp is cosposed of

iron formtion and is approsinatoly parallel to the basal ins. Clw swamp on this n.^,p rapreocnto open, bog land, devoid of wiy usder brush or trsos.

Rq^ icnal

Outcrops in this whole area are relatively ecr-rco and what outcrorso occur, are in groups along the crests of rid^a or ec-srpc. Sven then, tha outcrops ara not ler^e. The cost ccnspicuoug rod: md cost consistently outcropping rock is the bandod iron formation. It can ba follcued for nilea, eithor in its continuity, or in brcksa eatpents - l, by ground r^^netor.ster survey, 2 - projac^icn,aloa3 atr^o, of outcrops. Tlia bonded iron forn.'ticn vao apparently cost rasiatcnt to I do not think it is-l^a up coro than a fraction of ths rock in the region.

Probably the coat ccrrnon rock typo in th-^ area is tha basic to iatsroediata volcanica, alcn.^ x^ith. v^nryin^ proportions of intor-bod;led eodir-snta. These do net resist erosion, Tha nszt toot common rod; after tho volcrinica is probably1 granite, but not aa larijs araa plutono. Tha grc.nite3 are nore erosion rsoiote^t than the Bsdinsnts-volciuiica but still aro not conspicuous. Tha no:ct most coLzion rock is probably the bnsic intruslvaa (gabbro~diorite) Tlxe extant of this rock typa in area so heavily mantled with ovsrburdsn, is a cuoss.

Strilce faults are th3 coat co^^on rscctTaimble structural feature. Thsoe are extensivo and of lar^p diFansicas. 7olds ere vary difficult to define, tecsues S3oot, if not all, dips r.ra vortic-ol or no-^r vsrtical. Only v/hsra tha iron folia tion rakes a ^i-aat fle^x'^o era B fold bo detected end thon v^ are in dou'ot vhot^ar it is en aaticlino or eynclins.

5?o tha vaat, the granit-sg rad f^bbro-dioritea cccur e.3 very s-^.11 clilces to lar^ plucs up to several clnir-.s in erea. Thin VTIS o.lso true of the

ri3t'?norpjisa is nora evident in this area thr-n in t'.:3 Gnrnoto vnro fc-jni in tha iron fora t ion rnd the chai -3 3 s.re cl-.-u-ed tors'inolite .?.n.i t le schist's. Th,? b^.-sic volc-nics e^pos'-d in th*s north -c^d

vest of this cX-Jln bloo vero not profour.dly c^-"~i .-ei, hivever, thsy v^ro iv'dro-

(3)

thermal* altered to a carbonate rich rock. This was also true to the gabbro ^ound in the south east part of the claim bloc. This carbonate alteration seeas

j be regional.

Detailsd Gaolo^y

Tha oldest rock unit, is ths neries of basic to intermediate volcanics; pro bably submarine flows. They have basn altered and netanorphissd nore than usual for this region. Metanorphica has obliterated all structure and hydrothermal solutions have altered it to rock rich in carbonates, mostly in email gnash TO in s and fracture 3*

On top of the volcanics was laid a series of fine graihad clastic sediments; some of which had magnesium in tham, probably in the form of dolomite. These sediments have boon altered to chlorite-actinolite and talc schists, Uhere there is any appreciable amount of actinolite, there is usually an appreciable content of nagnetite. The nagnetite is probably of detrital origin, There is little quartz with the chlorite schists so thsy erode easily* Thay weather white and have been extensively intruded by granite dikes, parallel to the strike of the banded iron f oraation.

The most conspicuous rock unit is the banded iron fornatioa. It has beon traced completely across the area by ground mgnotonister eurvey. This has been correlated by the surface geologic survey. It extends unbroken to the eaot, along the south shore of Bsnbo'^r Lake. Wherever bedding was observed, which was often, ths forma tion was vertical or near vertical. The highly nagnetic strata is consistently about 200 feet thick, thinning slightly to ths west. Eovever there are portions which are not so magnetic, in fact, they may be the opposite, but ths appearance la the sane. This similar looking strata, non-ns.gnetic, hoyever, increases the avor- ago width of the iron foraation to about 350 or Jj-00 feet. Again ths width sesas to diminish to the west.

The banded iron formation consists of alternate bands of silica sand and det rital Eiagnstits or scaly limonite hcnatlte* The silica aaid is often pars and whits it is wall sorted and the grains are frostsd. The sand makes up about SOjS of ths formation in the nost magnetic and pyritifarouo strata, and alnost lOOJ? in othsr part a . This accounts for ths great nagnetic variation within this recognizable unit.

Vithin tho bonded iron formation, particularly in the eilica eand-sbaly limonite portions, thsro aro of ton short flat leaaos or pods of cynganetic pyrite, with v-sll formed cubes. These oulfioda, since thoy aro coarse, weather easily and nuch . detrital mgnetita is also released. It is this portion of the iron foraation that was intans-aly proopectsd^in the past, and trcn.ch.-3d.

There is also a euxinic facies in the banded iron foraation. This facies is fine grainad, the pyrite being found as nodules in a dsnso black, siliceous slataa, With the black slates are f ina bands of grosnish bltck chort r^id a very fine grained greenish sandatoae; alternating with thin bonda of d9trit-r.l n-gnetite. Tha Ejsj lenses are sulf ids-fros, This fine grained chsnically daposited facias io fotmi near tha top of the iron foraation. It is richest in cagnetita and his a vary regular contact with the overlying fino grained grssn qur.rtsita.

^~ Stratigraphicly above the "banded Iron formation, to the south, is a thick aad consistent "bad of a very fins grained green, dense quartzite, with very fine bedding coapoaed of biotite flakes. In every outcrop, the dip was vertical or near vertical, thus conforning with the banded iron formation. This formation consistently averaged 600 to 700 feet in thickness. It is very hard and weathers whitish. On a fresh outcrop that has been exposed for a long time, tha ^ine bio tite bedding gives this fonnation tha appearance and texture of a fine grained gneiss, and the uniform color suggests rhyolite. However, it is very dark, too consistent along strik-3, and gritty for a rhyolite. The grain size is BO snail It is almost a chert. She grain size is best seen on a weathered surface. The biotite bedding is not ouch more than one mica scale thick and ths rock is prob ably 95^ silica.

Tha next rock t/po is the basic intruoives. All of them were grouped to gether except for tha diabase. Outcrops were limited but those found were altered specially by carbonation. This Hakes correlation very likely with the gabbro- dlorite series of Jehann South Extension, One diorite outcrop was coarsely crystalline and deeply weathered. It may correlate with 6A, the late corer aa grain diorite, found in the Jehann South Extension.

The next rock unit is granite. Host of the granite outcrops were as dlkas in the sediments. Only in ono placa vere outcrops consistent enough to warrant call ing any aroa granitic* And hore, bocause of the siliceous nature of tha enclosing rock (probably sedimsntary schists) it is vory difficult to outline tha pluton, therefor, it was left indefinite. This granite is feuidL near the iron formation having hydrothermal pyrrhotite in veins and may be ths source of tha pyrrhotite*

The next rode unit Is serpentine. There were no larga nagnetic highs suggest ing ultra-basic intrusives; however, there were a nunber of very snail onos. Thsse line up along the Inferred inner contact of the graen quartzite, This saeas a likely place for their emplacement. Light green, slightly carbonated serpentine drift was found in several places. There was no fiber in any chunk. In view of ths ground magnetometer results, it appears unlikely that there is serpentine in eny quantity on this prospect.

The last rock type observed was diabase. It is intruded in dikes that seen to conform to tha regional strike instead of cross-cutting it. Evidence for this is a large east-west striking outcrop that has a porphyritic phase along its north face. This would bs difficult to explain if the dike were striking north-south.

II Structures

Ths iiost prominent structures on this prospect are two ssall isolated areas " of high nagnotic intensity, north of the regie, al iron formation. I have inter preted thasa as doubly plun^in^ synclinal troughs, tha very bottom being all that remains. Proa this interpretation I Lava Inferred that the top of the regional iron formation is to the north. On tha largsst of thsse oagnetic highs, tha upper iron formation", thsrs is one outcrop. This is along ths margin of the hi^h, The outcrop consists of a highly sheared, dark graoa quartzite, veinad with naas- ive pyrrhotite up to 6 inches wide. Th-are is a proopoct shaft sunk on this out crop. This groon quartzite could ba tha formation abovo tha rational iron forma tion, but it is too badly slioarsd to toll. Bscausa of tha lade of core outcrops, we nust coaclud.9 that this rock type could ba anywhere in tho Esdiasntary sarios.

To *'"t weat are two parallel iron formations, perhaps these are faulted rea-01 zenolitho preserved in enclosing granite. In the original reconnaissance

hrough this area, in the early 1920's, and published by the Ontario Bureau of Kinos, this one outcrop was noted and labeled as iron formation, I accept thia designation because h3 probably saw fresh, rock frcia the prospect shaft; however, this iron formation reaaant is probably highly altered, In order to find thia outcrop the reconnaissance mapper must have cone through when the prospsct shaft was "being sunk or soca after, when there still was interest in the area,

There also exists the possibility that the magnetite is of hydrothermal origin and ia an accessory to the pyrrhotite that is found in tha highly sheared rock. In the regional banded iron formation no pyrrhotite was found, so It is assusad that this pyrrhotite is of hydrothermal origin*

5fhe upper and larger recmant of "iron formation" has a distinct displacement. This is interpreted as a fault* The fault is assumed to continue south, termina ting the scalier "iron formation* remnant and cutting the regional iroa foraation In ths regional iron foraatioa there is little evidence of displacenent or fault ing, However, to the south, and on strike with the direction of apparent dis- pladsnent of the upper "iron f creation", there was observed soae very large barren boulders of white quartz. This is assunod to be the trace of tha sane fault ae displaces the upper "iron formation".

Jurther faulting is difficult or iepossible to detect, either fron aerial photos, magnetometer survey, and geologic survey, and ffoa correlation of all three There is the possibility of a large strike fault directly to the north of the regional iron forsation. Evidence for this la the clossness of volcanics to the regional formation at ths west end of ths claim bloc aai ths presence of sediments in the same relative position further east. The lowlands and connecting stream of Best Bonbow Lakes would follow this fault and ths upper "iron formation" rem nants would becone dovm-faulted remnants and not folds,

III Geophysical Correlation

She lack of outcrops throughout ths area very much hindered correlation of the ground aagnetoneter survey with rock typss and major structures. Ths ground magnetoaeter survey has bsen the only ground geophysical survey run so far,

There are s'ona north-couth trending magnetic lc-.;s of large dinonsio-is, but it is unsafe to call these granites because ths ecdineuts beneath the regional iron formation are siliceous end rich in carbonate or carbonate rich nin^rals. Besides the known granite outcrops aro not on lows. Thus I have left large areas blank.

IV

Ho inferred ssrpentina body of any sizs exists and thua this area io of little interest in the eaarch for fitor but the area docs hairo definite intoreot for base metals exploration.

5?he upper "iron forraation11 hao no outcrop to define it as an iron forsation It is of very limited estont baing 1200 feot long and ^50 fost v/ids at its vida st. Its magnetic intensity ia vory high and its area very clocoly defined by surround ing lo-.fo, A prospect shaft has boca sunk on t ho ed;;o of this hi^h whers sor.a thin stringer veins of p;.'rrhotit3 aro found in an intensely shor-rod q,uartsitG, A grab Bonplo of this pyrrhotite assayed 17jf gold par ton and nil in coppsr, nickel eilvor and cobalt.

"~~ It i s possible that the hl^h magnetic intensity of this closely defined area

oould be due to hydrothorwal magnetite accompanying further and more extensive .

sulphide aineralization. Since the prospect shaft was sunk on an outcrop at tho

very edge of the magnetic anomaly, it alone doss not tell what is there. Shat

happens to foe tha only outcrop (or the only one found "by the author), on this

anomaly.

Although the regional iron formation contains sulfides, they are of syngenetic

origin and only of momentary interest!

Conclusions

The claim "bloc vas not large enough and/or there was not enough rock exposed

to draw in or postulate any regional structures beyond the obvious. This means

that the very largest regional structures, only, were drawn in (regional iron

formation) and only the rock types near outcrops could "be psotulated. Beyond this

the area is best left "blank because it is not known how the magnetic mediums and

lows "behave in relation to tha rock types in the surrounding region. However,

our interest in the highs is veil served "by the map as it stands.

Ree onasndati ons.

This claim bloc has no further interest for asbestos fiber exploration.

Jfeither doss the regional iron feruption hold any further interest in base metal

exploration unless sonething of interest is found in tha upper "iron formation",

In that event, furhtsr attention to the regional iron formation would bs in J.M T s

interest.

It would, however, be in J.M. 1 s immediate interest to nake a reconnaissance

EM Burvey over the upper"iron fcreation" remnants and also a detailed nagnetoneter

survey, to find out just what night bo present. Such a limited area with so nany

signs of mineralization, with BO little information, is of definite interest.

The saw mill on Afcweska Lake is planning to build an all weather road into

the east shore of Eaarahan Lake next summer. Therefor, J.M.*s interest in this

area should be current, so that if further interest in this area doss develop,

due to further esrploration, then J.M. can be prepared, next winter to go in, put

down a hole and get- out again, quickly, if nothing develops.

rEonald E.

s