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Showing 1 to 20 of 88 for “"Chert"”.
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Chert Nodules in Carbonate Rocks of Illinois
Made available in DSpace on 2014-12-04T19:13:36Z (GMT). No. of bitstreams: 1 0025194.pdf: 3940680 bytes, checksum: 1b309db6cf4ec8d5efa889ca7fd22998 (MD5) Previous issue date: 1957
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Subsurface Analysis of Mississippian Tripolitic Chert in Northwest Arkansas
… focuses on the analysis of Boone tripolitic chert in the subsurface utilizing wireline data available from selected gas wells within the study area. The primary goal of this project is to determine and quantify the subsurface stratigraphic position of tripolitic chert from wells that cut a …
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Evolution and Anatomy of Early Terrestrial Arthropods: Insights from the Rhynie Chert
… is the Lower Devonian (ca. 408 Ma) Rhynie chert of Aberdeenshire, Scotland. Preserved in extraordinary three-dimensional detail by silica sinters from ancient hot springs, the Rhynie chert represents the earliest complex land animal ecosystem in the fossil record. Its diverse biota includes …
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Triple oxygen isotope measurements in chert: insights into the Snowball Earth glaciations
… for these silica cements. We posit that these cherts are precipitates either from syn-glacial, sub-ice meltwaters or deglacial fluids from the end of the Marinoan glaciation, providing useful insights into the chemical composition of these source waters and demonstrating the utility of chemical …
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Examining the diagnostic value of 87SR/86SR for midwestern blue-gray chert source determination
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms
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Analysis of Tripolitic Chert in the Boone Formation (Lower Mississippian, Osagean), Northwest Arkansas and Southwestern Missouri
… nearly complete sequence of Lower Mississippian chert-bearing carbonates deposited by a single 3rd order transgression and regression. An abundant amount of chert that has replaced limestone highlights the Boone, but little is understood about the timing and development of chert in Lower …
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Pilot Study using Elemental Geochemistry as a Means of Discriminating Chert Stratigraphy in the Roberts Mountains Allochthon, Nevada
Biogenic chert beds in the Roberts Mountain Allochthon (RMA) are analyzed for major and trace element geochemistry with the goal of developing a geochemical means to differentiate units. This detailed chemical profile will allow for the identification of unknown cherts through the use of chemical …
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Evaluation of different treatments to improve the durability of concrete having deleterious chert particles as its coarse aggregate
… of air-entrained concretes having poor quality cherts as course aggregates subjected to three different treatments for improving durability, the following conclusions have been derived: 1. Removal of cherts lighter than the BSSD specific gravity of 2.5 by heavy liquid definitely improved the …
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Crescent Hill Chert: A Geological and Cultural Study of a Raw Material Procurement Area in Yellowstone National Park, Wyoming
… (MYAP) conducted survey of the Crescent Hill chert outcrop (site 48YE729) in the northern portion of Yellowstone National Park. Occurring in a variety of colors and qualities, the chert precipitated within the Eocene-era Crescent Hill basalt formation. The procurement area encompasses 2,124.8 …
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Crescent Hill Chert: A Geological and Cultural Study of a Raw Material Procurement Area in Yellowstone National Park, Wyoming
… (MYAP) conducted survey of the Crescent Hill chert outcrop (site 48YE729) in the northern portion of Yellowstone National Park. Occurring in a variety of colors and qualities, the chert precipitated within the Eocene-era Crescent Hill basalt formation. The procurement area encompasses 2,124.8 …
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Heat Treatment of Ozark Cherts: An Archaeological Experiment in the Effects of Heat Treatment on Toolstone Flaking Properties
… two of which are Burlington and Jefferson City cherts. Burlington chert is typically considered a poorer quality chert than Jefferson City chert for stone tool production. I hypothesize that people heat-treated Burlington as well as Jefferson City chert to improve the flaking qualities of the …
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Lithologic Controls on Karst Groundwater Flow, Lost River Groundwater Basin, Warren County, Kentucky
… between these two formations are two bedded chert units, the Lost River Chert Bed (Elrod, 1899) within the Ste. Genevieve and the Corydon Chert Member (Woodson, 1983) of the St. Louis, which appear to be perching layers to shallow karst groundwater flow. Groundwater may be seen flowing on top …
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Spatial Distribution Of Debitage At A Chert Procurement Site And A Cultural History Assessment On Orange Lake In North Central Florida
… size categories. Further separation was based on chert type and thermal alteration. These data were evaluated in terms of a distance drop-off model using correlation to explore proximity to local chert sources. The results of these tests proved there was not a sole quarry location in the northwest …
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The Description and Interpretation of a Tertiary Siliceous Rock in Western North Dakota
… to the latter. It varies from an arenaceous chert to a sandy chert-cemented siltstone, the defining factor being the chert to detrital grain ratio. Macroscopically, it is typically dense, hard and dark gray in addition to containing numerous plant fossils. Exceptional occurrences are …
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Subsurface Sequence Stratigraphy and Reservoir Characterization of the Mississippian Limestone (Kinderhookian to Meramecian), South Central Kansas and North Central Oklahoma
… in the mid-continent are largely comprised of chert-rich carbonates of Osagean and Meramecan age. The conventional reservoir target is the Mississippian "chat," a high porosity, chert residuum interval found immediately beneath the Mississippian-Pennsylvanian unconformity. The unconventional …
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Geological reconnaissance and provenancing of potential Neolithic lithic sources in the Maltese Islands
… the petrological characteristics of Neolithic chert artefacts associated with the Temple Period (c. 4000-2500 cal BC) and their probable sources from the local Maltese chert formation as well as the main possible chert sources in Sicily. Were the chert and flint materials used by prehistoric …
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A Comparative Study of Silicified Rock Reservoir in Shunnan 4 well of Tarim Basin with Hydrothermal Chert Reservoir of Parkland Gas Field in Western Canada Sedimentary Basin
… the only comparable one is the hydrothermal chert reservoir interbedded among dolomite and dolomitic mudstone in the Wabamun Group of Upper Devonian, discovered in 1956 in Parkland, NW Western Canada sedimentary basin (WCSB). Due to limited reference in this chert reservoir, detailed work …
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A Petrologic and Diagenetic Study of the Onondaga Formation, New Jersey
… mudstones and siliceous mudstones with nodular chert, and three siliceous mudrocks including calcareous mudrocks, calcareous mudrocks with nodular chert, and cherty calcareous mudrocks. The mineralogy of these five lithofacies is roughly consistent amongst the sites. Carbonate minerals (calcite …
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Geochemical Analysis of Mississippian Cherts and Devonian-Mississippian Novaculites, Southern Midcontinent Region
… genetic relationship between the Boone Formation chert (206Pb/204Pb ~ 21.59, 207Pb/204Pb ~ 15.87, 208Pb/204Pb ~ 40.10) and the MVT ores. Due to the very low concentration of Pb in the Boone chert (~2 ppm) and the close proximity of samples containing radiogenic Pb to the tripolitic chert interval, …
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