2009 Portland GSA Annual Meeting (18-21 October 2009)

Paper No. 32
Presentation Time: 9:00 AM-6:00 PM

NEW 1:24,000 SCALE GEOLOGIC MAPS FOR THE BELFAIR AND BURLEY 7.5' QUADRANGLES IN MASON, KITSAP AND PIERCE COUNTIES, WASHINGTON


POLENZ, Michael1, ALLDRITT, Katelin1, HEHEMANN, Nicholas J.2, SARIKHAN, Isabelle1 and LOGAN, Robert L.1, (1)Division of Geology and Earth Resources, Washington Department of Natural Resources, 1111 Washington Street SE, PO Box 47007, Olympia, WA 98504-7007, (2)Geology, University of Montana, 32 Campus Drive, Missoula, MT 59812, michael.polenz@dnr.wa.gov

We present new 1:24,000 scale surficial geologic maps for the Belfair and Burley 7.5’ quadrangles in Mason, Kitsap and Pierce Counties, Washington. Mapping was carried out 2008 and 2009 by the Washington State Geologic Survey (Washington Division of Geology and Earth Resources, Department of Natural Resources) with matching funds from the United States Geological Survey’s Statemap cooperative mapping program, and both maps are available electronically as free PDF poster files. The Belfair quadrangle map can be downloaded from http://www.dnr.wa.gov/Publications/ger_ofr2009-7_geol_map_belfair_24k.pdf, the Burley quadrangle map from http://www.dnr.wa.gov/Publications/ger_ofr2009-8_geol_map_burley_24k.pdf. The maps improve on earlier mapping through four months of new field work, new age control data, and taking advantage of LiDAR data and other recent developments. The maps highlight deposits and landforms associated with a stagnant ice mass and ice-dammed lakes at the end of the Fraser glaciation, and how these affect drainage and other geologic characteristics. The maps identify scarps lineaments, and elevated relict beaches, stream terraces and alluvial fans that may have been uplifted by post-glacial tectonic activity. Current thinking on tectonic activity in the area is summarized by the text accompanying the maps.