Petrologic Intervals and Petrofacies in the Great Valley Sequence, Sacramento Valley, California

Abstract

Research Article| October 01, 1972 Petrologic Intervals and Petrofacies in the Great Valley Sequence, Sacramento Valley, California WILLIAM R DICKINSON; WILLIAM R DICKINSON Geology Department, Stanford University, Stanford, California 94305 Search for other works by this author on: GSW Google Scholar ERNEST I RICH ERNEST I RICH Geology Department, Stanford University, Stanford, California 94305 Search for other works by this author on: GSW Google Scholar Author and Article Information WILLIAM R DICKINSON Geology Department, Stanford University, Stanford, California 94305 ERNEST I RICH Geology Department, Stanford University, Stanford, California 94305 Publisher: Geological Society of America Received: 21 Oct 1971 Revision Received: 22 Feb 1972 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1972, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1972) 83 (10): 3007–3024. https://doi.org/10.1130/0016-7606(1972)83[3007:PIAPIT]2.0.CO;2 Article history Received: 21 Oct 1971 Revision Received: 22 Feb 1972 First Online: 02 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 DICKINSON, ERNEST I RICH; Petrologic Intervals and Petrofacies in the Great Valley Sequence, Sacramento Valley, California. GSA Bulletin 1972;; 83 (10): 3007–3024. doi: https://doi.org/10.1130/0016-7606(1972)83[3007:PIAPIT]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 Great Valley Sequence of Upper Jurassic to Upper Cretaceous strata is composed of clastic detritus eroded from the Sierran-Klamath belt, which was the site of a late Mesozoic magmatic arc. The sequence accumulated mainly as a prismatic wedge of turbidites in an asymmetric trough within the arc-trench gap. Stratigraphic variations in detrital sandstone mineralogy define five petrologic intervals, or nearly synchronous petrofacies, useful for regional correlation. By contrast, local lithofacies are markedly lenticular. The clastic debris in the sequence was derived mainly from volcanic and plutonic rocks in varying proportions. The parameters used to define the petrofacies include: (a) content of quartzose grains (Q), feldspar grains (F), and unstable lithic fragments (L) expressed as volumetric percentages of the Q-F-L population; (b) ratios of plagioclase to total feldspar (P/F) and volcanic rock fragments to total unstable lithic fragments (V/L), and (c) content of mica (M) expressed as volumetric percentage of framework sand grains. The most distinctive characteristics of the petrofacies recognized, and their approximate time-stratigraphic spans, are as follows: (1) Stony Creek (Tithonian-Neocomian): quartz-poor and feldspatholithic sandstones with high P/F, high V/L, low M; (2) Lodoga (Aptian-Albian): quartz-rich sandstones with high P/F; (3) Boxer (Cenomanian): two distinct variants with moderate P/F, one quartz-rich and the other quartz-poor and feldspatholithic; (4) Cortina (Turonian-Coniacian): two similar variants with moderate P/F, one with Q-F-L proportions nearly equal and the other quartz-poor and feld-spatholithic; (5) Rumsey (Santonian-Campanian): quartz-rich lithofeldspathic with low P/F and high M. The nature of the petrofacies and their age can be related to the petrology and timing of dated intrusive episodes with inferred volcanic accompaniments in the Sierra Nevada. The Stony Creek petrofacies contains mainly volcanic debris erupted during the Yosemite magmatic epoch, and the overlying Lodoga petrofacies contains mainly plutonic debris emplaced during the same epoch, but only exposed to erosion by subsequent dissection. The Boxer and Cortina petrofacies contain mixed and intercalated volcanic and plutonic debris derived mainly from rocks erupted or emplaced during the Huntington Lake magmatic epoch. The slight differences between the Boxer and Cortina petrofacies may indicate that plutonic contributions were partly from older rocks for the Boxer, but volcanic contributions were essentially the same for both. The Rumsey facies contains mainly plutonic debris, with subordinate volcanic debris, derived from igneous rocks of the Cathedral Range magmatic epoch. Except locally or slightly, petrofacies boundaries do not transgress time-stratigraphic boundaries in the region. A close linkage among major magmatic, tectonic, and depositional events in arc-trench systems is implied. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.