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Source map Wilson, F.H., and Weber, F.R., 2010, Unpublished data.
Symbol Ground Moraine
Unit name Ground moraine, marine innudated
Description Inferred to be poorly sorted, nonstratified, rock fragments ranging in size from coarse, meter-sized, subrounded to rounded fragments to fine sand and silt. Ground moraine, locally flooded to at least 100' asl
Lithology Unconsolidated

Correlated geologic units

Label Qgme
Description Morainal deposits inferred to have been modified during glacioestuarine inundation
Geologic age Late-Pleistocene
Geologic setting Unconsolidated
Lithology Form Importance
Gravel < Coarse-detrital < Unconsolidated Glacial, till Major
Sand < Coarse-detrital < Unconsolidated Glacial, till Major
Boulders < Coarse-detrital < Unconsolidated Glacial, till Minor
Silt < Fine-detrital < Unconsolidated Glacial, till Minor