Open AccessReconnaissance surficial geology, Tinney Hills, Nunavut, NTS 76-J
Author(s) -
D E Kerr
Publication year - 2022
Language(s) - English
Resource type - Reports
DOI - 10.4095/321821
Subject(s) - meltwater , geology , outwash plain , bedrock , landform , geomorphology , drumlin , erosion , glacial period , fluvial , ice sheet , glacier , oceanography , ice stream , seabed gouging by ice , physical geography , sea ice , structural basin , cryosphere , geography
The Tinney Hills map area consists primarily of glacially and meltwater scoured bedrock, discontinuous till in the southwest and central-east, and postglacial marine sediments in coastal lowlands and along river valleys inland. The boundaries of many tilldeposits are cut to bedrock by widespread subglacial meltwater erosion. Ridged till in particular, is often associated with eskers and other glaciofluvial sediments and meltwater erosion. Striations and streamlined till landforms indicate regional ice flow towards the north-northwest and northwest,and later crosscutting relationships recording minor variations locally. Orientation of eskers and outwash plains suggest ice recession was primarily southeastward. Small, isolated glacial lakes formed where retreating or stagnant ice temporarily blocked local drainage. Below 200 to 220 m elevation,the region was inundated by the sea during ice retreat. Glaciomarine and marine sediments consist of littoral beach and offshore sediments, winnowed till surfaces, and isolated deltas. Isostatic rebound caused marine regression, recorded by deltas and beaches at 210 to 220 m elevation, anddecreasing to current sea level.