Neogene Tectonic Evolution of the Salinian Block, West-Central California (1974)

Research Article| January 01, 1974 Neogene Tectonic Evolution of the Salinian Block, West-Central California Jeffrey D. Johnson; Jeffrey D. Johnson 1Department of Geology and Geophysics, University of Minnesota, Minneapolis, Minnesota 55455 Search for other works by this author on: GSW Google Scholar William R. Normark William R. Normark 1Department of Geology and Geophysics, University of Minnesota, Minneapolis, Minnesota 55455 Search for other works by this author on: GSW Google Scholar Author and Article Information Jeffrey D. Johnson 1Department of Geology and Geophysics, University of Minnesota, Minneapolis, Minnesota 55455 William R. Normark 1Department of Geology and Geophysics, University of Minnesota, Minneapolis, Minnesota 55455 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1974) 2 (1): 11–14. https://doi.org/10.1130/0091-7613(1974)2<11:NTEOTS>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 Email Permissions Search Site Citation Jeffrey D. Johnson, William R. Normark; Neogene Tectonic Evolution of the Salinian Block, West-Central California. Geology 1974;; 2 (1): 11–14. doi: https://doi.org/10.1130/0091-7613(1974)2<11:NTEOTS>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 600-km-long Salinian block is petrologically similar to the plutonic-volcanic arc complexes of the Sierra and Peninsular Ranges and is bounded on the east by the San Andreas fault. Neogene motion of only 300 km on the fault is insufficient to explain the present offset position of the Salinian block, assuming that it was originally contiguous with the Sierra and Peninsular Ranges. Models involving earlier pre-Eocene movements on an "ancestral" San Andreas fault can account for the basement offset, but a reconstruction based on such models leaves the Salinian block standing at least 100 km west of its counterparts. In addition, it does not explain how the present length of 600 km fits in a 300-km gap between the Sierra and Peninsular Ranges. Our model postulates that significant slivering and northwestward extension have occurred within the block during Neogene time, and that the block formed a westward-protruding bulge in the North American continental margin prior to collision of the Pacific and North American plates. A reconstruction of plate motions indicates approximately 1,000 km of relative North American–Pacific displacement in the last 30 m.y.; this displacement could easily account for the block's extension and basement offset. 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.