Geology Commons^™

Deep Structure Of Siletzia In The Puget Lowland: Imaging An Obducted Plateau And Accretionary Thrust Belt With Potential Fields, Megan L. Anderson, Richard J. Blakely, Ray E. Wells, Joe D. Dragovich

Geology Faculty Publications and Presentations

Detailed understanding of crustal components and tectonic history of forearcs is important due to their geological complexity and high seismic hazard. The principal component of the Cascadia forearc is Siletzia, a composite basaltic terrane of oceanic origin. Much is known about the lithology and age of the province. However, glacial sediments blanketing the Puget Lowland obscure its lateral extent and internal structure, hindering our ability to fully understand its tectonic history and its influence on modern deformation. In this study, we apply map-view interpretation and two-dimensional modeling of aeromagnetic and gravity data to the magnetically stratified Siletzia terrane revealing its …