- King County — Thumbnail History (historylink.org)
King County, located in Western Washington, covers some 2,100 square miles extending from the crest of the Cascade Range to Puget Sound, including Vashon Island. It is Washington’s most populous county and contains its largest city – Seattle. It is the commercial center of the Pacific Northwest with public and private enterprises including Boeing, Costco, Group Health Cooperative, Washington Mutual, Starbucks Coffee Co., Amazon.com, University of Washington, Microsoft, PACCAR Inc, Weyerhaeuser, Seattle City Light, and the Port of Seattle, which operates the nation’s eighth-largest port as well as Sea-Tac International Airport…
- The City of Shoreline is one of Seattle’s closest suburbs. Located immediately north of Seattle’s city limits, the area was settled first by homesteaders and soon after by vacationers. Over time a community formed, and although Seattle’s boundaries have pushed farther north, Shoreline has preserved its autonomy and, in the 1990s, incorporated as a city in its own right.
- Tukwila Formation—Andesitic to dacitic volcanic sandstone, siltstone, shale, tuff-breccia, tuff, volcanic mudflow (lahar), carbonaceous shales, and minor lava flows or sills. Typically massive; only local sedimentary interbeds indicate structure. K-Ar age on plagioclase from tuff-breccia at top of unit, about 3 km west of quadrangle, yielded an age of 42.0±2.4 Ma (Turner and others, 1983)