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Sedimentology, stratigraphy, and geochronology of the Proterozoic Mazatzal Group, central Arizona

2002; Geological Society of America; Volume: 114; Issue: 12 Linguagem: Inglês

10.1130/0016-7606(2002)114 2.0.co;2

1943-2674

Rónadh Cox, Mark W. Martin, Jana C. Comstock, Laura S. Dickerson, Ingrid L. Ekstrom, James H. Sammons,

Paleontology and Stratigraphy of Fossils

Research Article| December 01, 2002 Sedimentology, stratigraphy, and geochronology of the Proterozoic Mazatzal Group, central Arizona Rónadh Cox; Rónadh Cox 1Department of Geosciences, Williams College, Williamstown, Massachusetts 01267, USA Search for other works by this author on: GSW Google Scholar Mark W. Martin; Mark W. Martin 2Department of Earth and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA Search for other works by this author on: GSW Google Scholar Jana C. Comstock; Jana C. Comstock 3Department of Geosciences, Williams College, Williamstown, Massachusetts 01267, USA Search for other works by this author on: GSW Google Scholar Laura S. Dickerson; Laura S. Dickerson 4Geology Department, Colorado College, Colorado Springs, Colorado 80903, USA Search for other works by this author on: GSW Google Scholar Ingrid L. Ekstrom; Ingrid L. Ekstrom 5Department of Geology, Amherst College, Amherst, Massachusetts 01002, USA Search for other works by this author on: GSW Google Scholar James H. Sammons James H. Sammons 6Department of Geology, Washington and Lee University, Lexington, Virginia 24450, USA Search for other works by this author on: GSW Google Scholar GSA Bulletin (2002) 114 (12): 1535–1549. https://doi.org/10.1130/0016-7606(2002)114 2.0.CO;2 Article history received: 20 Jul 2001 rev-recd: 30 May 2002 accepted: 30 May 2002 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Rónadh Cox, Mark W. Martin, Jana C. Comstock, Laura S. Dickerson, Ingrid L. Ekstrom, James H. Sammons; Sedimentology, stratigraphy, and geochronology of the Proterozoic Mazatzal Group, central Arizona. GSA Bulletin 2002;; 114 (12): 1535–1549. doi: https://doi.org/10.1130/0016-7606(2002)114 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 Quartzite, conglomerate, and shale of the Mazatzal Group record the filling of a Prot erozoic intra-arc basin in central Arizona. U-Pb ages of zircons from rhyolite ash-flow tuff indicate that deposition began at 1701 ± 2 Ma. Basal deposits of the newly defined Pine Creek Conglomerate formed in an alluvial-fan setting, synchronous with the final phase of extrusive rhyolite volcanism and active faulting. After volcanic activity ceased, shallower-slope braided-stream environments developed in early Deadman Quartzite time. Subsequent marine transgression produced shallow subaqueous deposits of the upper part of the Deadman Quartzite. These were overlain by prodelta sediments of the Maverick Shale, indicating a phase of basin deepening. Finally, the Mazatzal Peak Quartzite was deposited as the basin shoaled again, first to shallow- marine and subsequently to fluvial conditions. The quartzite is diagenetic quartz arenite, originally deposited as lithic arenite and lithic arkose. The provenance was initially restricted, and earliest sediment was derived mainly from the subjacent Red Rock Group. When tectonic activity ceased, how ever, the surrounding highlands were planed down by erosion, and detritus from a wider variety of source rocks was funneled into the basin. This included contributions from arc-related supracrustal rocks of the Payson Ophiolite and East Verde River Formation, and finally a granitic basement input. Detrital quartz in the lower part of the Mazatzal Group is largely monocrystalline, and volcanic in origin. Polycrystalline quartz, associated with detrital feldspar and of probable continental affinity, is concentrated in the uppermost parts of the sequence. The life span of the intra-arc basin was on the order of 30 m.y., from the formation of the Payson Ophiolite at 1.73 Ga to the deposition of the upper Mazatzal Peak Quartzite sometime after 1.70 Ga. The pre-Mazatzal Red Rock Group represents the last stages of volcanic arc activity, and the Mazatzal Group records the transition from orogenic to nonorogenic sedimentation in central Arizona. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.