Holocene Pacific–North American plate interaction in southern Alaska: Implications for the Yakataga seismic gap

Abstract

Research Article| October 01, 1980 Holocene Pacific–North American plate interaction in southern Alaska: Implications for the Yakataga seismic gap John C. Lahr; John C. Lahr 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar George Plafker George Plafker 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar Author and Article Information John C. Lahr 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 George Plafker 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1980) 8 (10): 483–486. https://doi.org/10.1130/0091-7613(1980)8<483:HPAPII>2.0.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation John C. Lahr, George Plafker; Holocene Pacific–North American plate interaction in southern Alaska: Implications for the Yakataga seismic gap. Geology 1980;; 8 (10): 483–486. doi: https://doi.org/10.1130/0091-7613(1980)8<483:HPAPII>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The St. Elias, Alaska, earthquake (magnitude 7.1 Ms) on February 28, 1979, occurred along the complex Pacific–North American plate boundary between Yakutat Bay and Prince William Sound, rupturing only a fraction of the seismic gap identified in that region. To aid in evaluating the potential for, and likely site of, a future earthquake occurring in the remainder of the gap, we have formulated a kinematic model of neotectonic deformation in southern Alaska from available geologic and seismic data. In this model the part of the North American plate bordering on the Gulf of Alaska is divided into three subblocks, which are partially coupled to the Pacific plate. On the basis of the model, the gap-filling rupture or ruptures would most likely be along the north-dipping thrust faults of the Pamplona zone between Icy Bay and the eastern end of the Aleutian Trench. If the accumulated strain of 3.8 m postulated for this region were released suddenly in one event involving the remainder of the gap, the result would be an earthquake as large as magnitude 8. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.