found: Work cat.: 2006404375: Preliminary volcano-hazard assessment for Okmok Volcano, Umnak Island, Alaska, 2005:p. 1 (Okmok Volcano is an active volcano located on the northeast end of Umnak Island, about 100 kilometers southwest of Dutch Harbor. The volcano is capped by a large, circular caldera, 10 km in diameter and 500 to 800 m deep, that formed during catastrophic eruptions about 12,000 and 2,000 years ago.)
found: GNIS, July 17, 2006(Mount Okmok, summit, Aleutians West, Alaska, 53⁰28ʹ05ʺN, 168⁰10ʹ30ʺW. Okmok Caldera is in the center of this mountain.)
found: Wikipedia, July 17, 2006(Mount Okmok: location: Alaska, Aleutian Range; type: Shield volcano)
