GEOLOGICAL SURVEY OF CANADA PAPER REPORT OF ACTIVITIES, Part A: April to October, 1968 DEPARTMENT OF ENERGY, MINES AND RESOURCES.

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1 GEOLOGICAL SURVEY OF CANADA PAPER 69-1 Part A REPORT OF ACTIVITIES, Part A: April to October, 1968 DEPARTMENT OF ENERGY, MINES AND RESOURCES

2 @ Crown Copyrights reserved Availahlc by rn:~il from thc Quecn's Printer, Ottawa, from Cicological Survcy oi Canada, 601 Booth St., Ottawa. and at the following Canadian Government bookshops: HALIFAX 1735 Barrington Street MONTREAL Eterna- Vie Building, 1182 St. Catherine St. West OTTAWA Duly Building, Corner Mackenzie and Rideou TORONTO 221 Yonge Street WMNIPEG Mull Center Bldg., 499 Portage Avenue VANCOWER 657 Granville Street or through your bookseller Price $2 00 Catalogue No. M A Price subject to change without notice ROGER DUHALIEL, F.R.S.C. Queen's Printcr and Controller of Stationery Ottawa, Canada 1969

4 QUATERTARY GEOLOGY OF THE UPPER CHAUDIERE RIVER DRAINAGE BASIN, QUEBEC, (21 E, (east half)) Project W. W. Shilts Reconnaissance mapping of the surficial deposits of the Quebec portion of the eastern half of Sherbrooke map-area (21 E) was completed. Mapping has outlined a system of moraines and meltwater channels which mark former ice front positions at halts during the retreat of an active ice sheet. The highest and oldest of these systems is represented by discontinuous ridges of till and gravel and by meltwater channels which are preserved at altitudes of 1, 600 feet to 1, 800 feet on the west and north-facing slopes of the Boundary Mountains and on the east and north flanks of Mount Megantic. Prominent northeast-trending, ice- contact gravel and sand moraines through Ditchfield and gravel-till moraines near Marsboro and Moose Lake mark halts of backwasting ice or readvance positions. A broad, lobe-shaped area of chlorite-rich clay till and associated chlorite-rich silt till seems to represent a southerly glacier readvance from St. Ludger to or south of Lac Megantic. Abundant north-south striae north of the study area1 and similarly oriented weakly developed striae north of St. Ludger, suggest that the readvance may have been much more extensive. A thin till unit overlying ice-contact gravel and thin lake sediment in several places north of St. Ludger may be correlative with the clay till farther south. In the vicinity of Drolet, extensive slumping of thick Pleistocene sediments has been studied. Relief of pressure by the removal of easily erodible lake sediment has caused large and small scale slumping along the Chaudikre River and its tributaries. Some large slump blocks with apparent vertical displacements of over 150 feet are displaced away from Drolet River and cannot readily be explained by response to river erosion. Postdepositional compaction and/or plastic flow of the thick (180 feet) laminated clays, which commonly occur below 1, 400 feet in this region, are possible mechanisms for producing this large-scale faulting. Fault or slump scarps form the steep sides of asymmetric gullies and streams and are the loci of many small mudflows. Extreme care should be taken in planning and construction and in any modification of natural river channels in this area as even slight loading of slopes, or alteration of stream grade or position with respect to valley walls, has initiated and may cause further slumping, mudflows, and severe gullying.

5 Detailed study of surface boulder distribution has delineated anomalously high concentrations of pyroxenite and serpentinized peridotite between St. Ludger and the junction of the Samson and ChaudiBre rivers (Fig 1 The high concentration does not fit the general down-ice decrease in ultrabasic boulder frequency from the source area in thevicinityof Caribou Mountain. The anomaly could be related to a slight magnetic high southeast of Lake No. 2 and Douglas ~ake~. Brief reconnaissance of the magnetic high failed to show either boulder concentration or outcrop of ultrabasic rocks. add, N. R. : Surficial geology, Beauceville map-area, Quebec; Geol. Surv. Can., Paper (1964). L~t. Evariste, Frontenac and Beauce Counties, Quebec; Geol. Surv. Can., Aeromagnetic Map No. 153 G (1954) QUATERNARY STUDIES IN THE SOUTHWESTERN PRAIRIES, ALBERTA Project A.M. Stalker Field work in 1968 in the main continued the Quaternary stratigraphy and vertebrate paleontology studies of previous years. Dr. C. S. Churcher, Department of Zoology, University of Toronto, continued his association with the writer on this project as vertebrate paleontologist, although he was able to spend only a short period in the field, in the autumn. The writer had the privilege of having as archeological consultants Mr. B. Reeves and Mr. C. Eyman, both from Department of Archeology, University of Calgary. An archeological party under direction of Mr. Reeves participated in the excavations. Much of the study consisted of intensive examination of interglacial (Sangamon?) deposits at Mitchell Rluff, on the south side of South Saskatchewan River north of Medicine Hat, in NE 114 sec. 32, tp. 13, rge. 5, W. 4th mer. (50 7'45"N. ; 110" 38'401'W.). This study entailed removal of 8, 000 cubic yards of material to reach a 5-foot-thick gravel band that in other years had supplied numerous vertebrate fossils and what apparently are poorly-formed artifacts. That gravel band again surpassed expectations, yielding several hundred bones and additional chipped cherts and worked pieces of bone. In addition, deposits along the river, both older and younger, but particularly the basal gravels, yielded many bones.

Projects and

Projects and DRIFT PROSPECTING IN THE DISTRICT OF KEEWATIN - URANIUM AND BASE METALS Projects 700014 and 750074 W. W. Shilts and R. A. Klassen Studies of trace metal distribution in till were continued in the Yandle-Henninga