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At least 631 records · Page 35Linked to original sources
USGS1979

Glacial geology and stratigraphy of Western New York Nuclear Service Center and vicinity, Cattaraugus and Erie Counties, New York

A detailed glacial geologic map at a scale of 1:24,000, embracing a 165 square-mile area in Erie and Cattaraugus Counties, NY, shows 27 mapping units, including the till complex in which the West Valley radioactive-waste burial site is located. Stratigraphic relationships at 24 boreholes at the burial site and 6 newly described exposures indicate the age of the till complex to be early late Woodfordian (post-Kent, pre-Lake Escarpment, Valley Heads), equivalent to the Lavery glacial advance. Correlations of mapping units and measured sections with Woodfordian and older glacial and deglacial episodes are proposed. The Lavery till is confined to the valleys of Cattaraugus Creek and its major tributaries. At the waste-burial site in Buttermilk Creek Valley, the Lavery is an interfingering complex of clayey-silt till and thinner beds of deformed, poorly stratified lacustrine clay and silt. Ice readvance after the Kent glacial recession and Erie Interstade erosion imponded proglacial lake water in Buttermilk Creek Valley and covered post-Kent kame deltas and Erie channel gravels with as much as 130 feet of till. The Lavery till thins southward to a thickness of 80 feet at the waste-burial site and to less than 16 feet near the hamlet of West Valley. Water from the Lavery till may flow through subjacent Erie channel gravel and Kent-recessional kame delta sand to the bluffs along Buttermilk Creek, where discharge of water from these exposed pervious deposits appears to cause major slumps. (USGS)

New York↗
USGS1981

Stratigraphy, sedimentology, and paleomagnetism of the Coral Ridge sand body, eastern Taylor Valley, Victoria Land, Antarctica

A body of moderately well sorted and well stratified ice-cemented sand, here informally called the Coral Ridge sand body, was deposited across eastern Taylor Valley before the deposition of a veneer of glaciogenic deposits related to late Pleistocene incursions of the Ross Sea ice sheet. The Coral Ridge sand body is more than 50 m thick where preserved in a north-south trending ridge that is transverse to the long axis of the valley. The ridge forms a drainage divide that stands 100 m above sea level and separates the basin of Lake Fryxell on the west from the seacoast to the east. An erosion surface having about 35 m of abrupt local relief was apparently developed on the sand body before the latest incursions of Ross Sea ice. The Coral Ridge sand body accumulated in a fluviatile or possibly fluviomarine deltaic environment following deposition of coarse diamictons and interbedded layers of sand in a fjord that once occupied the site of Taylor Valley. From its sedimentary characteristics and topographic distribution, the sand was deposited across the valley following filling of the fjord. The 1) comparatively high degree of sorting, 2) general lack of clay and silt, and of very coarse detritus, and 3) common fluviatile cross-stratification, argue for stream transport and for accumulation principally above sea level. Coarse glacial detritus, which must have existed in the source area, was not transported to the area of sand deposition. Very fine glacial detritus that presumably was transported with the sand was deposited some place beyond the area of sand deposition. Evidence bearing on the direction of transport, and thus the source area, has not yet been developed. The source could have been a grounded ice sheet in the Ross Sea to the east, or alternatively, the source could have lay to the west in the area of the Lake Fryxell basin at a time when the basin was occupied by a more extensive Taylor Glacier. Evidence bearing on the age of the Coral Ridge sand body also is not fully developed. West of the Coral Ridge divide, the upper 2-3 m of a 14-mthick section of Coral Ridge sand near the top of hole DVDP-11 is reversely polarized. All other beds of the ice-cemented sand have been found to be normally polarized. Two possibilities exist: 1) the Coral Ridge sand body was deposited during late Pliocene time, mainly during a time of normal polarity of the Gauss polarity epoch, or 2) the sand body is much younger and was deposited during the Bruhnes normal polarity epoch of Pleistocene time, less than 730,000 years ago (in which case, the reversely polarized strata are anomalous). Additional subsurface and surface geological and paleomagnetic study is required to resolve the problems of age and source, critical to deciphering the late Cenozoic glacial and structural history of Taylor Valley and environs.

Victoria Land↗