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 Detterman, R.L., Miller, T.P, Yount, M.E., and Wilson, F.H., 1981, Quaternary geologic map of the Chignik and Sutwik Island quadrangles, Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I-1292, 1 sheet, scale 1:250,000.
Symbol ad
Unit name Drift, Alaskan glaciation (Neoglacial)
Description Unsorted, nonstratified coarse to fine angular debris within cirques and in valleys in front of modern glaciers. Forms arcuate lobes and end moraines of unstable and nonvegetated rubble generally within 1 to 1.5 km of modern glaciers. Locally two sets of end moraine present
Lithology Unconsolidated

Correlated geologic units

Label Qhg
Description Drift, neoglacial or so-called Alaskan glaciation
Geologic age Holocene
Geologic setting Unconsolidated
Lithology Form Importance
Boulders < Coarse-detrital < Unconsolidated Glacial Major
Gravel < Coarse-detrital < Unconsolidated Glacial Indeterminate, major