Unconsolidated surficial deposits, undivided

Unit symbol: Qs
Age range Quaternary (1.806 to 0 Ma)
Lithology: Unconsolidated
Group name: Unconsolidated and poorly consolidated surficial deposits
Unconsolidated, poorly to well-sorted, poorly to moderately well-stratified deposits; consist predominantly of alluvial, colluvial, marine, lacustrine, eolian, and swamp deposits. May include some glacial deposits. Also includes widespread glacial and periglacial deposits that consist of end, lateral, and ground moraine, outwash, rock glacier deposits, and other glacial and periglacial deposits as well as glacially scoured bedrock that may be covered with thin, glacially derived deposits. These glacial deposits are of Holocene and Pleistocene age and may include small areas of potentially latest Tertiary deposits. Map unit locally includes reworked volcanic debris as well as block and ash flows. On generalized map, shown as part of unit QTs

Source map information

Source map Richter, D.H., Preller, C.C., Labay, K.A., and Shew, N.B., 2005, Geology of Wrangell-Saint Elias National Park and Preserve, southcentral Alaska: U.S. Geological Survey Scientific Investigations Series Map SIM-2877, 15 p., 1 sheet, scale 1:350,000.
Symbol Qcr
Unit name Copper River deposits
Description Interbedded glaciolacustrine, glacial, and alluvial deposits. Includes deposits of glacial Lake Atna (Nichols, 1989; Williams and Galloway, 1986); historically complex basin built from numerous lake stages in response to multiple glacial advances and retreats. Locally overlain by small fine-grained alluvium and pond deposits (Qfl). Interbedded by the Mount Wrangell valley-fill lavas (Qwwv) along western margin of Mount Wrangell, especially in Chetaslina River valley area. Clay-pebble silt and diamicton, containing local to regionally distributed beds of gravel and sand
Lithology Unconsolidated

Correlated geologic units

Label Qgl
Description Glaciolacustrine deposits
Geologic age Pleistocene to Holocene
Geologic setting Unconsolidated
Lithology Form Importance
Sand < Coarse-detrital < Unconsolidated Lacustrine Major
Silt < Fine-detrital < Unconsolidated Lacustrine Major
Clay < Fine-detrital < Unconsolidated Lacustrine Indeterminate, major