Discovery of Extensive Pockmark Fields in Southern Puget Sound

Quasi-linear methane pockmark chains without active gas emissions were discovered in four south Puget Sound inlets adjacent to the Tacoma and Olympia fault zones Well-preserved morphology and local sedimentation rates imply that they formed in the past 50-100 years, a window with three major earthquakes (1949, 1965, 2001) We hypothesize that M6.5-7.1 earthquakes promoted vertical gas/fluid movement and accumulation, causing crater formation via roof collapse as they leaked