Subduction geometry of the Yakutat terrane, southeastern Alaska

Research confirms that the Yakutat Block subducts continuously from Prince William Sound to Icy Bay, extending the southeastern Alaska subduction zone 300 km further than previously known. The study used broadband seismic data and advanced imaging techniques—including three-dimensional P-wave field modeling and common conversion point stacking—to map the slab's geometry. Findings reveal a gradual increase in dip angle (11°–16°) from west to east, placing the Yakutat Block at the correct depth to explain magmatism in the Wrangell volcanic field. The data also show clear separation between the subducted Yakutat Block and the North American Plate under the Alaska Range, suggesting that deformation along the Denali fault is not linked to Yakutat coupling. Additionally, the study indicates sediment stripping on the block's western side and ductile lower-crustal thickening (>60 km) near Mount Saint Elias.

Bauer, M. A., Pavlis, G. L., & Landes, M. (2014). Subduction geometry of the Yakutat terrane, southeastern Alaska. Geosphere, 10(6), 1161–1176. https://doi.org/10.1130/ges00852.1