Geodetic constraints on areal changes in the Pacific–North America plate boundary zone: What controls Basin and Range extension?

Research Article| October 01, 2007 Geodetic constraints on areal changes in the Pacific–North America plate boundary zone: What controls Basin and Range extension? Corné Kreemer; Corné Kreemer 1Nevada Bureau of Mines and Geology, and Seismological Laboratory, University of Nevada, Reno, Nevada 89557, USA Search for other works by this author on: GSW Google Scholar William C. Hammond William C. Hammond 1Nevada Bureau of Mines and Geology, and Seismological Laboratory, University of Nevada, Reno, Nevada 89557, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Corné Kreemer 1Nevada Bureau of Mines and Geology, and Seismological Laboratory, University of Nevada, Reno, Nevada 89557, USA William C. Hammond 1Nevada Bureau of Mines and Geology, and Seismological Laboratory, University of Nevada, Reno, Nevada 89557, USA Publisher: Geological Society of America Received: 09 Mar 2007 Revision Received: 14 May 2007 Accepted: 17 May 2007 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 The Geological Society of America, Inc. Geology (2007) 35 (10): 943–946. https://doi.org/10.1130/G23868A.1 Article history Received: 09 Mar 2007 Revision Received: 14 May 2007 Accepted: 17 May 2007 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Corné Kreemer, William C. Hammond; Geodetic constraints on areal changes in the Pacific–North America plate boundary zone: What controls Basin and Range extension?. Geology 2007;; 35 (10): 943–946. doi: https://doi.org/10.1130/G23868A.1 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 Using ∼1500 geodetic velocities we model the present-day spatial patterns of areal changes inside the Pacific–North America plate boundary zone. From this model we show that between the central Gulf of California and the Queen Charlotte Islands there is no significant net change in surface area. This zero net areal-change result allows us to relate regions of areal growth to areas of equivalent contraction elsewhere within the plate boundary zone. We find that areal growth of the Basin and Range province (BRP) and its eastern margin (∼5.2 ± 0.1 × 103 m2/yr) is balanced by areal reduction near northwestern California between 38°N and 42°N. The San Andreas fault system south of 38°N and the plate boundary zone north of ∼42°N (including the Juan de Fuca and Gorda Ridge systems) each have no significant net areal change. Our results suggest a kinematic relationship between extension in the BRP and contraction near the northern California Coast Ranges and Klamath Mountains. From these observations we propose that, although BRP extension may be caused by internal forces, the southernmost Cascadia subduction zone provides a "window of escape" that acts as a stress guide to BRP extension as well as northwestward Sierra Nevada motion. Such a dynamic model is consistent with independent findings that (1) the least principal horizontal stress orientations in the BRP are toward northern California, (2) extension directions in the BRP have changed orientation to track the northward migration of the Mendocino triple junction, and (3) the southernmost Cascadia subduction zone is a relatively weak plate boundary. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.