Sevier belt exhumation in central Utah constrained from complex zircon (U-Th)/He data sets: Radiation damage and He inheritance effects on partially reset detrital zircons

Abstract

Research Article| March 01, 2015 Sevier belt exhumation in central Utah constrained from complex zircon (U-Th)/He data sets: Radiation damage and He inheritance effects on partially reset detrital zircons William R. Guenthner; William R. Guenthner 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA †Current address: Department of Geology, University of Illinois, Urbana-Champaign, Champaign, Illinois 61820, USA; wrg@illinois.edu. Search for other works by this author on: GSW Google Scholar Peter W. Reiners; Peter W. Reiners 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar Peter G. DeCelles; Peter G. DeCelles 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar Jerry Kendall Jerry Kendall 2ExxonMobil Exploration Company, Houston, Texas 77060, USA Search for other works by this author on: GSW Google Scholar GSA Bulletin (2015) 127 (3-4): 323–348. https://doi.org/10.1130/B31032.1 Article history received: 10 Nov 2013 rev-recd: 25 Apr 2014 accepted: 29 Jul 2014 first online: 08 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 William R. Guenthner, Peter W. Reiners, Peter G. DeCelles, Jerry Kendall; Sevier belt exhumation in central Utah constrained from complex zircon (U-Th)/He data sets: Radiation damage and He inheritance effects on partially reset detrital zircons. GSA Bulletin 2015;; 127 (3-4): 323–348. doi: https://doi.org/10.1130/B31032.1 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 Thermochronologic dates of partially reset detrital grains are often difficult to interpret because of the potential for variation in inherited predepositional dates and kinetic behaviors of grains from diverse source terrains. In this study, we present several examples of complex detrital zircon (U-Th)/He date distributions from sedimentary rocks that have been heated to temperatures in or near the zircon He partial retention zone, leading to several types of date-eU correlations caused by variations in predepositional inherited age and radiation-damage–induced He diffusion kinetics. These examples are from three subvertical transects in mountain ranges in central Utah: the Wasatch Range near Provo, Utah, the Oquirrh Mountains, and the Stansbury Mountains. Each range lies in the hanging wall of one of three major thrust sheets that compose part of the Charleston-Nebo salient, a segment of the Cretaceous Sevier fold-and-thrust belt. Zircon grains from two of these transects (the Stansbury and Oquirrh Mountains) show large date variations that can be at least partially understood with a radiation-damage–based model for He diffusion in zircon. We combine the output from this model with a new approach for understanding partially reset data sets that relies upon the concept of an “inheritance envelope.” The transect from the Wasatch Range is relatively simple and does not require an inheritance-based interpretation. We document a pulse of 5 km of exhumation in this range at ca. 100 Ma. Time-temperature (t-T) constraints from inheritance envelopes in the Oquirrh Mountains transect suggest a pulse of exhumation beginning at either 110 or 100 Ma. Finally, for the Stansbury transect, the inheritance envelope approach yields inconclusive results; some aspects of the model generate inheritance envelopes that match the measured data set, whereas others do not. Despite their complexity, the t-T histories for these nonideal data sets represent some of the only in situ constraints on the timing of Cretaceous exhumation of Sevier-style deformation in the U.S. Cordillera. In the case of the Oquirrh and Wasatch Range data sets, these direct measurements of thrust sheet t-T histories offer some insight into the evolution of the Sevier fold-and-thrust belt of central Utah. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.