Geochemical investigation of a Neoproterozoic glacial unit: The Mineral Fork Formation in the Wasatch Range, Utah

Research Article| April 01, 2002 Geochemical investigation of a Neoproterozoic glacial unit: The Mineral Fork Formation in the Wasatch Range, Utah Grant M. Young Grant M. Young 1Department of Earth Sciences, University of Western Ontario, London, Ontario N6A 5B7, Canada Search for other works by this author on: GSW Google Scholar Author and Article Information Grant M. Young 1Department of Earth Sciences, University of Western Ontario, London, Ontario N6A 5B7, Canada Publisher: Geological Society of America Received: 16 Jan 2001 Revision Received: 03 Oct 2001 Accepted: 23 Oct 2001 First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (2002) 114 (4): 387–399. https://doi.org/10.1130/0016-7606(2002)114<0387:GIOANG>2.0.CO;2 Article history Received: 16 Jan 2001 Revision Received: 03 Oct 2001 Accepted: 23 Oct 2001 First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Grant M. Young; Geochemical investigation of a Neoproterozoic glacial unit: The Mineral Fork Formation in the Wasatch Range, Utah. GSA Bulletin 2002;; 114 (4): 387–399. doi: https://doi.org/10.1130/0016-7606(2002)114<0387:GIOANG>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 SocietyGSA Bulletin Search Advanced Search Abstract The Mineral Fork Formation is an isolated unit of Neoproterozoic glaciogenic rocks in the Wasatch Range in northwestern Utah. Geochemical analyses of diamictite and mudstone samples were carried out to document its major and trace element geochemistry. Comparison of the lower and upper parts of the formation, which have been ascribed to different tectonic and sedimentological settings, revealed no striking differences, but the analyzed samples show a gradual upward increase in CaO, MgO, Fe2O3, MnO, and P2O5 and a decrease in SiO2. TiO2:Al2O3 ratios that suggest a provenance throughout the formation with an average composition slightly more mafic than average upper crust. The mudstones are more K rich than the diamictites. Calculation of a chemical index of alteration (CIA) is complicated by the presence of carbonate minerals. After making corrections for carbonate content, CIA values range from 65 to 70. These values are higher than those from Paleoproterozoic glaciogenic deposits. Some mudstones in the upper part of the formation are Fe rich (∼15% Fe2O3), approaching the composition of iron formations. The ferruginous nature supports previous correlation with Fe-rich glaciogenic rocks of the Rapitan Group in the northern Canadian Cordillera. Trace elements, including rare earth elements, suggest that the materials in the Mineral Fork Formation were largely derived from a post-Archean source. Most of the widespread glaciogenic rocks of the Neoproterozoic were derived from older sedimentary materials, whereas the deposits of the earlier great glacial episode in the Paleoproterozoic contain a much higher proportion of crystalline materials. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.