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A Combined Petrographical-Geochemical Provenance Study of the Newland Formation, Mid-Proterozoic of Montana
223 A combined petrographical-geochemical provenance study of the Newland Formation, Mid-Proterozoic of Montana JüRGEN SCHIEBER Department of Geology, The University of Texas at Arlington (UTA), Arlington, Texas 76019, U.S.A. Abstract - A provenance study was conducted on the Mid-Proterozoic Newland Formation, in which petrographical features of sandstones and geochemical characteristics of shales were integrated to arrive at an internally consistent interpretation. Sandstones of the Newland Formation are typically arkosic sands and arkoses with very well rounded quartz and feldspar grains and only minor amounts of extrabasinal rock fragments. The predominant feldspar types are K-spar and microcline, feldspar grains are smaller than quartz grains, and feldspars show little alteration due to weathering. Detrital modes of Newland sandstones (QFL diagrams) indicate that they were derived from a stable cratonic source. These petrographical features imply a source area dominated by granites and granitoid gneisses, semi-arid to arid climate, tectonic quiescence and overall peneplain conditions. Shales of the Newland Formation are dominated by illite, quartz silt, and fine crystalline dolomite. They have small La/Th rations, relatively large Hf contents, and small contents of Cr, Co, and Ni, all indicative of derivation from crust of granitic composition. Small TiO2/AI2O3 ratios also suggest source rocks of granitic composition. The average chemical index of alteration (CIA) for Newland shales is 71.8, which in light of the probable granitoid source indicates modest amounts of chemical weathering. Relatively large Si02 contents and large K20/Na20 ratios reflect derivation from stable cratonic areas and tectonic quiescence. Thus, in general, the petrography of sandstones and geochemistry of shales provides the same provenance clues for the Newland Formation. -
Composition and Provenance of Sand from Wells, Santa Clara Valley, California Karen Marie Locke San Jose State University
San Jose State University SJSU ScholarWorks Master's Theses Master's Theses and Graduate Research Fall 2011 Composition and Provenance of Sand from Wells, Santa Clara Valley, California Karen Marie Locke San Jose State University Follow this and additional works at: https://scholarworks.sjsu.edu/etd_theses Recommended Citation Locke, Karen Marie, "Composition and Provenance of Sand from Wells, Santa Clara Valley, California" (2011). Master's Theses. 4100. DOI: https://doi.org/10.31979/etd.ttvz-k3gg https://scholarworks.sjsu.edu/etd_theses/4100 This Thesis is brought to you for free and open access by the Master's Theses and Graduate Research at SJSU ScholarWorks. It has been accepted for inclusion in Master's Theses by an authorized administrator of SJSU ScholarWorks. For more information, please contact [email protected]. COMPOSITION AND PROVENANCE OF SAND FROM WELLS, SANTA CLARA VALLEY, CALIFORNIA A Thesis Presented to The Faculty of the Department of Geology San José State University In Partial Fulfillment of the Requirements for the Degree Master of Science by Karen M. Locke December 2011 © 2011 Karen M. Locke ALL RIGHTS RESERVED The Designated Thesis Committee Approves the Thesis Titled COMPOSITION AND PROVENANCE OF SAND FROM WELLS, SANTA CLARA VALLEY, CALIFORNIA by Karen M. Locke APPROVED FOR THE DEPARTMENT OF GEOLOGY SAN JOSÉ STATE UNIVERSITY December 2011 Dr. David Andersen Department of Geology Dr. Ellen Metzger Department of Geology Dr. Richard Sedlock Department of Geology ABSTRACT COMPOSITION AND PROVENANCE OF SAND FROM WELLS, SANTA CLARA VALLEY, CALIFORNIA by Karen M. Locke Medium sand samples from well cores taken in the Santa Clara Valley, California, were studied to determine their composition and, if possible, their provenance. -
Ocean Drilling Program Scientific Results Volume
Taylor, B., Fujioka, K., et al, 1992 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 126 9. PETROGRAPHY AND PROVENANCE OF VOLCANICLASTIC SANDS RECOVERED FROM THE IZU-BONIN ARC, LEG 1261 Kathleen M. Marsaglia2 ABSTRACT Modal compositions of volcaniclastic sands recovered on Leg 126 of the Ocean Drilling Project (Izu-Bonin island arc and Sumisu Rift) are similar to those from other intraoceanic island arcs and associated marginal basins. These sands are dominantly composed of volcanic-lithic and plagioclase-feldspar grains derived from the Izu-Bonin magmatic arc and intrarift volcanoes. The glass color of volcanic fragments ranges from black (tachylite) to brown to colorless; individual samples usually contain a mixture of glass colors. Two of the forearc sites (792 and 793) are more heterogeneous with respect to glass color than the backarc/Sumisu Rift sites (788, 790, and 791). Site 787 forearc sands are dominantly composed of tachylite grains; their unique composition may be attributed either to winnowing by submarine-canyon currents or to a volcanic island source. There is an increase in the proportions of pumice/colorless glass, felsitic grains, and quartz within sediments of the incipient backarc basin (Sumisu Rift), as compared with the forearc-basin sites. INTRODUCTION (1988), Nishimura and Murakami (1988), and Taylor, Fujioka, et al. (1990) interpret the layered clastic units recovered in cores on the The Izu-Bonin intraoceanic arc, located on Iwo Jima Ridge, is a Sumisu basin floor to be the products of turbidity currents and northward extension of the Mariana arc system (Fig. 1). A series of gravity-flow processes. -
Redalyc.PETROGRAPHY and PROVENANCE of the SIWALIK
Boletín de Geología ISSN: 0120-0283 [email protected] Universidad Industrial de Santander Colombia Kazi Tamrakar, Naresh; Kumar Syangbo, Dev PETROGRAPHY AND PROVENANCE OF THE SIWALIK GROUP SANDSTONES FROM THE MAIN BOUNDARY THRUST REGION, SAMARI RIVER AREA, CENTRAL NEPAL, SUB-HIMALAYA Boletín de Geología, vol. 36, núm. 2, julio-diciembre, 2014, pp. 25-44 Universidad Industrial de Santander Bucaramanga, Colombia Available in: http://www.redalyc.org/articulo.oa?id=349632714002 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Boletín de Geología ISSN: 0120-0283 Vol. 36, N° 2, julio-diciembre de 2014 URL: boletindegeologia.uis.edu.co PETROGRAPHY AND PROVENANCE OF THE SIWALIK GROUP SANDSTONES FROM THE MAIN BOUNDARY THRUST REGION, SAMARI RIVER AREA, CENTRAL NEPAL, SUB-HIMALAYA Naresh Kazi Tamrakar1; Dev Kumar Syangbo1 Suggested citation: Tamrakar, N.K., and Syangbo, D.K. 2014. Petrography and provenance of the Siwalik Group sandstones from the Main Boundary Thrust region, Samari River area, Central Nepal, sub-Himalaya. Boletín de Geología, 36 (2): 25-44. ABSTRACT The Siwalik Group is a thick sedimentary sequence forming the youngest mountain belt, extending throughout the East- West of the foothills of the Himalayas, and is separated from the Lesser Himalaya to the north by the Main Boundary Thrust, and the Indo-Gangetic Plain to the south by the Himalayan Frontal Thrust. The Siwalik Group was formerly the foreland basin sediment of the Himalayas. -
Two Point-Counting Methods for Modal Analyses of Holocene Sands: Their Comparison and Evaluation
85 堆 積 学 研 究,48号,85-93,1998 J.Sed.Soc.Japan.No.48,85-93,1998 Two point-counting methods for modal analyses of Holocene sands: their comparison and evaluation Mayumi Nirasawa*, Yoko Minato* and Koji Yagishita* Two-different point-counting methods of thin-sectioned sands have been argued in evaluat- ing their grain size effects and aims. The traditional method that reflects the dependence of modal composition on grain-size quite differs from the Gazzi-Dickinson method that shows the total independence of grain-size in thin-section analyses. Sets of goals by the two meth- ods do not seem to be the same; the traditional method aims to demonstrate the effect of depositional environments, climates and diagenesis of sediments, whereas the primary target of the Gazzi- Dickinson method is mainly to clarify tectonic settings in provenances. In an attempt to avoid some confusions raised by the two different point-counting methods , we reveal that there will be no significant difference of petrographic data between two meth- ods if we restrict the sand or sandstone samples less than 2.0 phi of mean diameter. Key words: modal analyses, Gazzi-Dickinson method, traditional method, grain size, thin- section 1978) . Believers of the latter method are the stu- INTRODUCTION dents of William R. Dickinson, who developed his It has been well known that there are two counting method at Department of Geology, methods of point-counting in determing detrital Stanford University. The students of his school modes of sand and sandstone thin-sections maintain that modal composition can be demon- (Ingersoll et al., 1984) . -
Front Matter
SHORT NOTES ON ALASKA GEOLOGY 1997 Edited by James G. Clough and Frank Larson Cover design by Ann-Lillian C. Schell Professional Report 118 Recent research on Alaska geology Front cover: View of central Kigluaik Mountains on the Seward Peninsula. Peaks are composed of Thomp- son Creek Orthogneiss of Late Proterozoic to Early Precambrian age and metamorphosed at upper am- phibolite facies conditions about 91 million years Fairbanks, Alaska ago. Photograph by J.M. Amato. 1998 i Foreword This volume of Short Notes on Alaska Geology 1997 is the tenth volume in the series begun by the Alaska Division of Geological & Geophysical Surveys (DGGS) in 1976. The Short Notes series was started as a vehicle in which to sum- marize significant observations on Alaska geology that oth- erwise might not find their way into accessible literature. From the outset an effort has been made to attract the contri- butions of geologists from the public, private, and academic sectors of Alaska’s geologic community. DGGS has a mandate to advance the knowledge of the ge- STATE OF ALASKA ology of Alaska. Clearly, that task is too large to undertake Tony Knowles, Governor alone. By working together, much more can be accom- plished. I would like to reemphasize the inclusive nature of DEPARTMENT OF this publication. I strongly encourage readers of this issue NATURAL RESOURCES to become participants in our next volume. In a very real John T. Shively, Commissioner sense, the Short Notes series is a publication of Alaska’s DIVISION OF GEOLOGICAL & entire geologic community. GEOPHYSICAL SURVEYS Milton A. Wiltse Authors, as well as readers, benefit from contributions. -
Processes Controlling the Composition of First-Cycle Sediments Deposited in an Arid-Climate, with Implications for Provenance Reconstruction Studies
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 12-2011 Processes controlling the composition of first-cycle sediments deposited in an arid-climate, with implications for provenance reconstruction studies Aubrey Lynn Modi [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Part of the Geochemistry Commons, Geology Commons, and the Sedimentology Commons Recommended Citation Modi, Aubrey Lynn, "Processes controlling the composition of first-cycle sediments deposited in an arid- climate, with implications for provenance reconstruction studies. " Master's Thesis, University of Tennessee, 2011. https://trace.tennessee.edu/utk_gradthes/1087 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Aubrey Lynn Modi entitled "Processes controlling the composition of first-cycle sediments deposited in an arid-climate, with implications for provenance reconstruction studies." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Geology. Chris M. Fedo, Major Professor We have read this thesis and recommend its acceptance: Devon M. Burr, Hap Y. McSween Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a thesis written by Aubrey L.