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John W Counts

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The dataset consists of geochemical and isotopic data from fine-grained sediments and glendonite crystals collected at Carter Creek on the North Slope of Alaska. Total Organic Carbon (TOC) values in the measured section were found to range between 0.5 and 3.5%, with a shift towards lower values in the uppermost 5 m of the section. Stable isotopes (13C) in organic matter were relatively stable throughout the section, ranging between -25.5 and -26, with a slight 0.3 per mil positive shift within this range approximately 57 m from the base of the section. Glendonites themselves were analyzed for δ13Ccarb and δ18Ocarb, with δ18O values relatively consistent between -0.22 and +1.28, and a much wider range of δ13C values...
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U-Pb isotopic data from zircon grains from the sediment bedload of seven modern rivers: the Susquehanna, Potomac, Roanoke, James, Peedee, Tar, and Cape Fear, as well as from three samples taken from beaches in Albemarle and Pamlico Sounds (North Carolina), two Pleistocene core samples, and three samples on the ocean-facing foreshore of the Outer Banks barrier islands (North Carolina and Virginia). All analyses were conducted either by the University of Arizona LaserChron Center or Geosep Services (GSS).
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The USGS Gulf Coast Source Rock Database (GCSRD) is an online repository for all publicly available source rock data (outcrop and subsurface) from the states of Florida, Georgia, Alabama, Mississippi, Louisiana, Arkansas, and Texas. "Source rock data" are defined in this context as data that include any of the following measured or calculated parameters: -total organic carbon (TOC), -various pyrolysis measurements (Tmax, S1, S2, S3, HI, OI), -vitrinite or bitumen reflectance values. All data in the GCSRD have been extracted from previously published peer-reviewed literature or as USGS-released data sets; no new measurements are included. The underlying data set is presented as an interactive, map-view application...
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This data release contains zircon U-Pb (n=1467) and Hf (n=332) data for five modern rivers (Connecticut, Susquehanna, Roanoke, Peedee, and Chattahoochee) draining the Appalachian mountain belt. The data show that zircon crystallization ages are characterized by several discrete populations that often correspond with orogenic episodes in the Mesoproterozoic and Paleozoic, with distinct differences between the various rivers sampled. ɛHf values are more consistent geographically, but differ between the Grenville and Paleozoic (Taconic, Acadian, and Alleghenian) orogenies.
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This dataset contains results from a stratigraphic section of the Hue Shale located along the Jago River in the Arctic National Wildlife Refuge at 69.9099, -143.3947 (WGS84). Sample heights were measured with a tape measure in a continuous succession. Zircon grains from volcanic ashes were analyzed via laser ablation at either the University of California, Santa Barbara (UCSB) or the University of Arizona Laserchron Center (ALC) using a Photon Machines Analyte 193-nm Excimer laser and Nu Instruments Plasma HR MC-ICPMS. Zircon grains from volcanic ashes were analyzed via chemical abrasion at the Berkeley Geochronology Center using a Sector 54 TIMS. Bulk mudstone samples were subject to a variety of analyses. Total...
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