Younger glacial drift

Till. Hard, blue-gray to gray concrete-like mixture of clay, silt, sand, and gravel deposited as end or recessional moraine. Principally Wisconsin in age.
State Washington
Name Younger glacial drift
Geologic age Pleistocene
Lithologic constituents
Major
Unconsolidated > Coarse-detrital (Glacial-till)gravel and sand
Unconsolidated > Fine-detrital (Glacial-till)silt and clay
Comments Possibly some outwash from the Fraser Glaciation (which encompassed the Vashon and Sumas Stades) occurs in this unit; most of it, however, is mapped within WAQg1o.
Stratigraphic units Vashon drift (moraine and till members); Sumas Drift (in part)
References

Huntting, M.T., Bennett, W.A.G., Livingston, V.E.Jr., and Moen, W.S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000.

Easterbrook, D.J., 1976a, Quaternary Geology of the Pacific Northwest, in Mahaney, W.C., ed., Quaternary Stratigraphy of North America: Stroudsberg, PA, Dowden, Hutchinson and Ross, p. 441-462.

Jones, M.A., 1999, Geologic Framework for the Puget Sound Aquifer System, Washington and British Columbia: U. S. Geological Survey Professional Paper 1424-C, 31 p., 18 pls.

NGMDB product
Counties King - Kitsap - Lewis - Mason - Pierce - Skagit - Snohomish - Stevens - Thurston - Whatcom