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., Ratte, J.C., Leeman, W.P., and Menzies, Martin, 2000, Geologic map of the McCarthy D-1 quadrangle, Alaska: U.S. Geological Survey Miscellaneous Geologic Investigations Series Map I-2695, 1 sheet, scale 1:63,360.
Symbol Ql
Unit name Landslide deposits
Description Includes large slump and debris avalanche deposits. Particularly common along steep north flank of mountain escarpment south of Beaver Creek. Slump deposits consist chiefly of masses of volcanic rock as much as hundreds of meters wide; deposits are chiefly diamicton and rubble
Lithology Unconsolidated

Correlated geologic units

Label Qls
Description Landslide deposits
Geologic age Pleistocene to Holocene
Geologic setting Unconsolidated
Lithology Form Importance
Boulders < Coarse-detrital < Unconsolidated Landslide Major
Gravel < Coarse-detrital < Unconsolidated Landslide Major
Silt < Fine-detrital < Unconsolidated Landslide Minor
Clay < Fine-detrital < Unconsolidated Landslide Incidental