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ABSTRACTS OF DMR REPORTS

The following are abstracts of DMR reports by the Geological Survey published or reprinted during the past year or scheduled to be released before 31 December, 1979:

Beck, L.S. (1969; reprinted 1979): Uranium Deposits of the Athabasca Region; Sask., Dep. Min. Resour., Rep. 126, 139 p., 38 figs., 40 plates, 16 tables, 3 geol. maps.

The Athabasca region is an important metallogenic largely pre-tectonic. In view of this, and because of the province of uranium and contains numerous epigenetic inherent structural differences between the two types of vein-type pitchblende deposits, some of which arc of geological environment, it is considered that the stable economic proportions, as well as many syngenetic occur­ blocks acted as relatively rigid units during the Hudsonian rences of uraninite in country rock and in pegmatite. This in contrast to the linear belts which were heavily faulted, report synthesizes existing geological information con­ mylonitized, and extensively granitized. Pitchblende­ cerning the region and presents the writer's own data bearing solutions were liberated during the final stages of collected over a four-year period as Resident Geologist at the Hudsonian granitization at about 1780 m.y. ago and Uranium City for the Saskatchewan Department of Mineral followed the crystallization of syngenetic uraninite in Resources and the results of subsequent work carried out at gneissic and granitic rocks transitionally. As the uranium the University of Leeds. The regional distribution, litho­ mineralization is related genetically to the Hudsonian logical and structural control, mineralogy, geochemistry, gra:iitization and mylonitization, the deposits are virtually and genesis of the uranium deposits are discussed and a restricted to the linear belts. The Hudsonian granites appear revised structural history of the region is proposed. The to be largely of metasomatic or replacement origin and thus known occurrences of uranium are listed and their locations it is likely that the various types of uraninite-bearing are shown on maps and the pitchblende deposits are occurrences represent stages of re-crystallization in the described individually. transformation (granitization) of country rock to granite and that a late stage in the granitization process was the The region forms part of the Churchill structural release of pitchblende-bearing solutions. province of the and is underlain by a sequence of regionally metamorphosed and Early pitchblende was deposited mainly from colloidal granitized rocks, the basement complex, which is charac­ sols, whereas later pitchblende, accompanied by a wide terized by a dominant northeast-trending 'grain' imparted variety of metallic accessory minerals, was probably trans­ by the Hudsonian (1750 - 1950 m.y. ago). In ported in aqueous solution as a hexavalent uranyl ion places, the peneplaned basement complex is overlain complexed under high pressures of C02 , and precipitated unconformably by flat-lying or gently folded, essentially by means of loss of pressure and catalytic reaction with elastic sequences, the so-called cover rocks. Basic dykes, ferrous iron. Maximum and minimum indicated temper­ intruded about 1400 - 1500 m.y. ago cut all rocks of the atures of deposition are 475° and 120°C,-although much of region. the JJitchblende was probably emplaced between 250° and On the basis of geological mapping and aeromagnetic 350 C. The open-space type of deposition in faults and interpretation of un-mapped areas, the basement complex is attendant structures together with textural features suggest divisible into two types of geological and structural that most of the deposits were fanned at relatively shallow environment: (1) the linear belts, consisting of a wide depths, probably less than 10,000 feet. variety of rock types including metasedimentary and metavolcanic rocks, paragneisses, basic intrusive rocks, and Since their formation, syngenetic systems (the uraninite­ granites, and characterized structurally by isoclinal folding, bearing deposits) have remained essentially 'closed' with intense faulting, brecciation, and mylonitization; and {2) low mobility of lead, but pitchblende deposits have been areas formed by similar amounts of granite, migmatite, and rejuvenated at several times by minor tectono-thermal paragneiss, the stable blocks, which are less heavily events including downwarping of the basement prior to faulted. Moreover, the bulk of the rocks of the linear belts deposition of the cover rocks, folding aria faulting of the are only weakly to moderately metamorphosed whereas cover rocks, intrusion of diabase, and late movements along many of the rocks in the stable blocks are in the granulite faults; the latest reworking may have taken place during the facies. In view of these significant differences the two last one hundred million years. environments are considered to represent different struc­ tural levels in the crust prior to the Hudsonian orogeny. Investigation of selected pitchblendes by X-ray powder diffraction methods show that they h-ave- a fairly uniform Whole-rock Rb-Sr measurements indicate two periods of particle size of about l(f5 cm which appears to be granite emplacement; one at 1820 ± 100 m.y. ago, independant of the degree of oxidation of the pitchblende. coincident with the Hudsonian tectonism, and the other at Cell-edge dimensions of two pitchblendes were determined 2200 ± 100 m.y. ago. The granitic rocks of the linear belts and gave values of 5.34A and 5.41A respectively. are mainly of the younger type whereas both types are Numerous Vickers Hardness detem1inations carried out on represented in the stable blocks. The relative proportion of pitchblendes from ten deposits, yielded reasonably con­ pre-tectonic and syn-tectonic granite in the stable block sistent values with test-loads of 200 gm or greater and range areas is not known although several large batholiths may be from 501 - 874 with a mean of 688. - 223 -

Denner, M.J. (1978): Environmental Aspects of Oil and Gas Production in Saskatchewan; Sask., Dep. Miner. Resour., Mis. Rep. 78-5, ~·, 8 figs., 6 plates.

The relationship of oil nnd natural gas to t11e en­ This report concentrates on that latter aspect. Its vironment is complex . main thrust is a portrayal of the activities of the petroleum industry in Saskatchewan within the Tl1e energy and petrochemical usages of these context of sound environmental safeguards. Other commodities are basic to the enjoyment of modern energy alternatives to oil and natural gas also have living standards and profoundly affect the quality of environmental impacts which are taken into ac­ life of every individual. Pollution control and count in the formulation of a total energy policy by ecological protection are another part of the the government. picture. The production of oi l and natural gas, with all the attendant social and economic benefits, need not cause extensive environmental damage. An important function of government 1s a super­ visory and regulatory role in attaining this goal.

Denner, M.J. (1978): Mineral Resources of Saskatchewan; Sask., Dep. Miner. Resour., Misc. Rep. 78-11, ~. 8 figs., 11 tables.

This booklet provides a general review of the principal mineral commodities of the province, namely: crude oil and natural gas, lignite, potash, sodium su]phate, uranium, base and precious meta]s and nickel. Commodities are described under the following h~adings: history, origin or geol ogy, produc­ tion and r eserves. Maps, graphs and tables illustrate various aspects of the provincial mineral industry.

Denner, M.J. and Reeves, P.L. (1979): Mineral Resources of Saskatchewan; Sask., Dep. Miner. Resour., Misc. Rep. 79-11, ~' 8 figs., 11 tables.

Denner, M.J. and Reeves, P.L., (1979): Uranium Reserves and Potential of Northern Saskatchewan; Sask., Dep. Miner. Resour., Misc. Rep.,~- 6 figs., 2 tables.

Fuh, Tsu-Min (1979): Geology of the Gilbert Lake Area; Sask., Dep. Miner. Resour., Rep. 187.

Precambrian rocks of the Gilbert Lake West area have been divided into three mappable units: biotite gneisses. hornblende gneisses and ultramafic rocks. Acid ic pegmatites, which may in part be a result.of metamorphic segregation or a product of granitization, pervade the area. Three directions of folding were distinguished. Northwest-trending isoclinal folds are found in the western and southern portions of the map area. northerly-trending asymmetric folds in the north-central to northeastern parts of the area, and large scale northeasterly-trending folds refolded the earlier folds. Mineral assemblages identified indicate that the rocks are in the amphibolite facies. Rocks in most of the southern half of the area have been partially melted or granitized. Minor amounts of disseminated pyrite and pyrrhotite occur in the hornblende gneisses and migmatitic rocks. - 224 -

Fuh, Tsu-Min (1979): Geology of the Pagato River area; Sask., Dep. Miner. Resour., Rep. 207, ~' 3 tables, 10 plates, 1 geol. map.

The Pr ecambrinn rocks recognized in the Pagato River Area comprise rnctnmorphosed sediments. diorite. granod1orite and pegmatite . The metasediments, which are of l

* Fuzesy, A. and Young, R. (1979): Athabasca Formation Drill Hole Index; Sask., Dep. Miner. Resour., Misc. Rep. 79-2, ~·

This index has been compiled to facilitate reference to data available from drilling in the Athabasca Formation of Northern Saskatchewan. Details of each drill hole have been summarized from records, logs and reports submitted as assessment work. This list includes non-confidential drill holes as of April 1st, 1979. The files referred to may be examined in the assessment work section of the Department of Mineral Resources in Regina, 12th Floor, Toronto-Dominion Bank Building, 1914 Hamilton Street, and at their field offices in (La Ronge and Northern Reindeer Mining Districts i.e. NTS 64E, 64L, 64M, 74F, 74G, 74H) and Uranium City (Athabasca Mining District i. e . NTS 741, 74J, 74K, 74N, 740, 74P).

* Fuzesy, A. and Young, R. (1979): Index to Assessment Work in the Reindeer Mining District of Saskatchewan; Sask., Dep. Miner. Resour., Misc. Rep. 79-3, ~-

*Fuzesy, A. and Young, R. (1979): Index to Assessment Work in the La Ronge Mining District of Saskatchewan; Sask., Dep. Miner. Resour., Misc., Rep. 79-4, ~-

*Incorporated as Geological Survey Branch report since transfer of Records Section from Mines Branch on 1 April, 1979. - 225 -

*Fuzesy, A. and Young, R. (1979): Index to Assessment Work in the Athabasca Mining District of Saskatchewan; Sask., Dep. Miner. Resour., Misc. Rep. 79-5, 201 p.

Kupsch, W.O. (1979): Annoted Bibliography of Saskatchewan Geology (1970-1976 inclusive); Sask., Dep. Miner. Resour., Rep. 9 (Supplement, 1979), 140 p., 12 figs.

The Annotated Bibliography of Saskatchewan Geology (Supplement, 1979) lists references dealing with the geology of Saskatchewan from 1970 to and including 1976. It also includes a few references of dates earlier than 1970 and is a supplement to the Annotated Bibliography of Saskatchewan (1823-1970 incl.) compiled by W. 0. Kupsch and published by the Saskatchewan Department of Mineral Resources as Report no. 9 (Revised Edition, 1973). The references are arranged alphabetically by author and are accompanied by short annotations taking the form of expanded titles, rather than synopses of the scientific results recorded in the references. Indexes to the references are provided according to geographic area, as well as subjects. All published geologic maps and descriptive well logs of any part of the stratigraphic section are indexed separately. The present Supplement includes an outline of the National Topo­ graphic System but no index map covering the whol.:? province has been included. Such a map accompanies Report no. 9, Revised Edition, 1973. An outline of the Land Survey Systems of Saskatchewan has been added.

Munday, R.J. (1978): The Shield Geology of the Ile-a-la-Crosse (east) area, Saskatchewan; Sask., Dep. Miner. Resour., Rep. 189, ~. 2 figs., 13 plates, 2 geol. maps.

A major shear zone, the Needle Falls Shear Zone, has been traced running 020 ° through the mapped area. The terrain east of the shear zone is ascribed to the Rottenstone domain and is characterized by felsic gneisses and migmatites with ap­ parently little economic potential.

Suprocrustal gneisses and felsic basement west of the shear belong to the Mudjatik domain. The Wollaston Lake Fold Belt which lies against the shear zone is part of this domain. Supracrustals and their basement are well exposed in the less metamorphosed eastern margin of the fold belt, but relations remain obscure in the complexly deformed and highly metamorphosed main area of the Mudjatik domain which underlies the western part of the mapped area.

Basal conglomerates in the supracrustal sequence are anomalously radio­ active due to placer-type accumulations of radioactive accessory minerals, but are non-economic. Psammites above these conglomerates at Duddridge Lake carry potentially economic uranium and copper mineralization . Pegmatites close to the supracrustal unconformity are also commonly radioactive and a boss of leucogranite at the north end of Sandfly Lake may represent a mobilized con­ centration of this material. Cale-silicate layers in the supracrustals carry traces of chalcopyrite. A fault breccia at Pinehouse Lake is permeated by fluorite. - 226 -

Paterson, D.F., Kendall, A.C. and Christopher, J.E. (1978): The Sedimentary Geology of the La Loche Area, Saskatchewan; _S_a_s_k_._,~D_e_P~·-M~i_n_e_r_.~R_e_s_o_u_r~'' Rep. 201, ~' 13 figs., 2 tables, 15 plates, _l~g~e_o_l_.~a_n_d~_i_s_o~p_a_c_h~m_a...... ___p.

The La Loche area, NTS sheet 74C, can be divided geologica!ly into a north-eastern half composed of Precambrian igneous and metamorphic rocks and a south-western half of sedimentary strata. Only the latter was studied, the surficial geolo:]y from field data in the summer of 1975 and the subsurface from the available well-data. The surficial deposits consist almost entirely of a blanket of glacial sands and gravels, reworked in places into fluvial sands and lag deposits, and covered in many topographic depressions with a vegetative infill. and strata have been exposed in the Clearwater River Valley by removal of the glacial cover. These strata are mostly dolomites with coarse basal quart­ zose elastics in the case of the Devonian and quartzose sandstones, locally bituminous, in the case of the Cretaceous.

In the subsurface, the Cretaceous elastics overlie the Devonian rocks which range in lithology from limestones and dolostones to siltstones and coarse basal sandstones. The Devonian is bounded above by a sub-Cretaceous unconformity and below by that on the Precambrian. The Cretaceous elastics comprise a basal sandstone assigned herein to the Lower Mannville unit and is equivalent to the Mc­ Murray Formation. Above this lies the Upper Mannville unit which is composed of shale (Clearwater shale) at the base and upper sandstone equated with the Grand Rapids Formation of Alberta. The lithologies of the units are discussed, their stratigraphic correlation, isopach and structure maps and economic con­ siderations are presented.

Stauffer, M.R., Langford, F.F., Coleman, L.C. and Mossman, D.J. (1979): Geology of the Area Around Amiskit Island, Reindeer Lake, Saskatchewan; Sask. Dep. Miner. Resour., Rep. 191, ~' 5 figs., 1 table, 16 plates, 1 geol. map.

The area is located in northeastern Saskatchewan and is bounded on the east by the - Saskatchewan border. It is underlain by Precambrian gneisses of .meiasedimentary and volcanic origin which have been intruded by numerous plutons of trondhjemite, pegmatite, and other types. Amphibolite grade metamorphism has affected all the rocks in the area and the three fold episodes have resulted in complex deformation. Metamorphism and intrusion occurred mainly during the second fold episode. No mineral occurrences of high economic potential were discovered during the survey.

The following DMR reports were open filed by the Saskatchewan Geological Survey during the past year or are scheduled to be released before 31 December, 1979:

OF 79/1 Assessment of the Technical and Economic Feasibility of the Technical and Economic Feasibility of Peat Resource Development in Northern Saskat­ chewan Communities; Saskmont Engineering Co. Ltd., March, 1979.

OF 79/2 Forsythe, L.H. (open file): Geology of the Lac La Range (east) - Hunter Bay - Cartier Lake Areas. - 227 -

ACKNOWLEDGMENTS

Senior Assistants who assisted project leaders in the field are named on the accompanying maps. Full acknowledgment for assistance in the field is expected to be made in the final reports.

The editors are particularly grateful for assistance given in the editing of the report by division heads and Mr. Dean Potter. The report was typed by Mrs. Jagdish Bilkhu with assis­ tance from Mrs. Audrey Wickham and Mrs. Beverly Lusok. Messrs Jim Bedo, Pat Kydd and other staff of the departmental Carto­ graphic Division prepared many of the figures and assisted in the assembling of the maps.