Research Article| November 01, 2006 Cenozoic exhumation of the northern Sierra Nevada, California, from (U-Th)/He thermochronology M. Robinson Cecil; M. Robinson Cecil 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar Mihai N. Ducea; Mihai N. Ducea 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar Peter W. Reiners; Peter W. Reiners 2Department of Geology and Geophysics, Yale University, New Haven, Connecticut 06520, USA Search for other works by this author on: GSW Google Scholar Clement G. Chase Clement G. Chase 3Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar Author and Article Information M. Robinson Cecil 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Mihai N. Ducea 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Peter W. Reiners 2Department of Geology and Geophysics, Yale University, New Haven, Connecticut 06520, USA Clement G. Chase 3Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Publisher: Geological Society of America Received: 22 Jul 2005 Revision Received: 09 Jan 2006 Accepted: 01 Feb 2006 First Online: 03 Oct 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (2006) 118 (11-12): 1481–1488. https://doi.org/10.1130/B25876.1 Article history Received: 22 Jul 2005 Revision Received: 09 Jan 2006 Accepted: 01 Feb 2006 First Online: 03 Oct 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation M. Robinson Cecil, Mihai N. Ducea, Peter W. Reiners, Clement G. Chase; Cenozoic exhumation of the northern Sierra Nevada, California, from (U-Th)/He thermochronology. GSA Bulletin 2006;; 118 (11-12): 1481–1488. doi: https://doi.org/10.1130/B25876.1 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 SocietyGSA Bulletin Search Advanced Search Abstract Apatite and zircon (U-Th)/He ages from a 100-km-long range-perpendicular transect in the northern Sierra Nevada, California, are used to constrain the exhumation history of the range since ca. 90 Ma. (U-Th)/He ages in apatite decrease from 80 Ma along the low western range flanks to 46 Ma in the higher elevations to the east. (U-Th)/He ages in zircon also show a weak inverse correlation with elevation, decreasing from 91 Ma in the west to 66 Ma in the east. Rocks near the range crest, sampled at elevations of 2200–2500 m, yield the youngest apatite helium ages (46–55 Ma), whereas zircon helium ages are more uniform across the divide. These data reveal relatively rapid cooling rates between ca. 90 and 60 Ma, which are consistent with relatively rapid exhumation rates of 0.2–0.8 km/m.y., followed by a long period of slower exhumation (0.02–0.04 km/m.y.) from the early Paleogene to today. This is reflected in the low-relief morphology of the northern Sierra Nevada, where an Eocene erosional surface has long been identified. A long period of slow exhumation is also consistent with well-documented, widespread lateritic paleosols at the base of Eocene depositional units. Laterites preserved in the northern Sierra Nevada are the product of intense weathering in a subtropical environment and suggest an enduring, soil-mantled topography. We interpret this exhumation history as recording a Late Cretaceous to early Cenozoic period of relatively rapid uplift and unroofing followed by tectonic quiescence and erosional smoothing of Sierran topography through the Neogene. Well-documented recent incision appears to have had little effect on (U-Th)/He ages, suggesting that less than ∼3 km has been eroded from the Sierra Nevada since the early Cenozoic. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.