2015/05/01 by Aaron Brody, Christopher J. Pluhar, Greg M. Stock +1 · 14 citations
Engineering · Earth and Planetary Sciences · #Geophysical Methods and Applications #Seismic Waves and Analysis #Seismic Imaging and Inversion Techniques #National park #Geological survey #Library science #Archaeology #History #Geology #Geography #Geophysics #Computer science
paper · doi:10.2113/gseegeosci.21.2.111
published in Environmental and Engineering Geoscience 21(2), 111-127 (Geological Society of America)
openalex publication_date 2015/05/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Research Article| May 01, 2015 Near-Surface Geophysical Imaging of a Talus Deposit in Yosemite Valley, California ANNA G. BRODY; ANNA G. BRODY Department of Earth and Environmental Sciences, California State University, Fresno, 2576 East San Ramon Avenue, Mail Stop ST-24, Fresno, CA 93740 Search for other works by this author on: GSW Google Scholar CHRISTOPHER J. PLUHAR; CHRISTOPHER J. PLUHAR 1 Department of Earth and Environmental Sciences, California State University, Fresno, 2576 East San Ramon Avenue, Mail Stop ST-24, Fresno, CA 93740 1Corresponding author email: [email protected]. Search for other works by this author on: GSW Google Scholar GREG M. STOCK; GREG M. STOCK National Park Service, Yosemite National Park, 5083 Foresta Road Box 700, El Portal, CA 95389 Search for other works by this author on: GSW Google Scholar W. JASON GREENWOOD W. JASON GREENWOOD Advanced Geosciences, Inc., 2121 Geoscience Drive, Austin, TX 78726 Search for other works by this author on: GSW Google Scholar Author and Article Information ANNA G. BRODY Department of Earth and Environmental Sciences, California State University, Fresno, 2576 East San Ramon Avenue, Mail Stop ST-24, Fresno, CA 93740 CHRISTOPHER J. PLUHAR 1 Department of Earth and Environmental Sciences, California State University, Fresno, 2576 East San Ramon Avenue, Mail Stop ST-24, Fresno, CA 93740 GREG M. STOCK National Park Service, Yosemite National Park, 5083 Foresta Road Box 700, El Portal, CA 95389 W. JASON GREENWOOD Advanced Geosciences, Inc., 2121 Geoscience Drive, Austin, TX 78726 1Corresponding author email: [email protected]. Publisher: Association of Environmental & Engineering Geologists First Online: 02 Mar 2017 Online ISSN: 1558-9161 Print ISSN: 1078-7275 © 2015 Association of Environmental & Engineering Geologists Environmental & Engineering Geoscience (2015) 21 (2): 111–127. 10.2113/gseegeosci.21.2.111 Article history First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation ANNA G. BRODY, CHRISTOPHER J. PLUHAR, GREG M. STOCK, W. JASON GREENWOOD; Near-Surface Geophysical Imaging of a Talus Deposit in Yosemite Valley, California. Environmental & Engineering Geoscience 2015;; 21 (2): 111–127. doi: 10.2113/gseegeosci.21.2.111 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 SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract Talus at the base of cliffs in Yosemite Valley, CA, represents rock fall and debris avalanche accumulation occurring since the glacial retreat after the last glacial maximum. This ongoing mass wasting subjects humans and infrastructure to hazards and risk. In order to quantify post-glacial rock-fall rates, talus volumes are needed for the deposits of interest. We used three near-surface geophysical methods (ground penetrating radar, electrical resistivity, and seismic refraction) to locate the basal contact of talus below Glacier Point, near Curry Village in the eastern Yosemite Valley. The coarseness of the talus deposit limited our ability to use these methods in some areas, and the geometry at the base of the cliff restricted our ability to conduct seismic refraction and electrical resistivity across the talus-bedrock boundary there. Nonetheless, we were able to detect the basal boundary of talus on top of both bedrock and glacio-fluvial sediment fill. Geophysical imaging revealed an apparent onlapping relationship of talus over aggrading post-glacial sediment fill, and our data support the proposition of approximately 5 m of valley floor aggradation since deglaciation. The bedrock-talus contact is characterized by a dip of 52–64°, consistent with the dip of the cliff surface above the talus apex. Ground penetrating radar and resistivity were the most diagnostic methods, in addition to being the most rapid and easiest to implement on this type of deposit. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.