Search Results - "Present, Theodore M."

Large Carbonate Associated Sulfate isotopic variability between brachiopods, micrite, and other sedimentary components in Late Ordovician strata by Present, Theodore M., Paris, Guillaume, Burke, Andrea, Fischer, Woodward W., Adkins, Jess F.

“…•Isolated small amounts of different components from Late Ordovician limestones.•Measured texture-specific Carbonate Associated Sulfate (CAS) sulfur isotope…”
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Non-lithifying microbial ecosystem dissolves peritidal lime sand by Present, Theodore M., Gomes, Maya L., Trower, Elizabeth J., Stein, Nathan T., Lingappa, Usha F., Naviaux, John, Thorpe, Michael T., Cantine, Marjorie D., Fischer, Woodward W., Knoll, Andrew H., Grotzinger, John P.

“…Microbialites accrete where environmental conditions and microbial metabolisms promote lithification, commonly through carbonate cementation. On Little…”
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A high-resolution record of early Paleozoic climate by Goldberg, Samuel L., Present, Theodore M., Finnegan, Seth, Bergmann, Kristin D.

“…The spatial coverage and temporal resolution of the Early Paleozoic paleoclimate record are limited, primarily due to the paucity of well-preserved skeletal…”
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Iron: Life's primeval transition metal by Johnson, Jena E, Present, Theodore M, Valentine, Joan Selverstone

“…Modern life requires many different metal ions, which enable diverse biochemical functions. It is commonly assumed that metal ions' environmental…”
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Variability in Sulfur Isotope Records of Phanerozoic Seawater Sulfate by Present, Theodore M., Adkins, Jess F., Fischer, Woodward W.

“…The δ34S of seawater sulfate reflects processes operating at the nexus of sulfur, carbon, and oxygen cycles. However, knowledge of past seawater sulfate δ34S…”
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Primary microfossiliferous chert in the Aptian Barra Velha Formation by Moore, Kelsey R., Crémière, Antoine, Present, Theodore M., Barnett, Andrew, Bergmann, Kristin D., Amthor, Joachim, Grotzinger, John

“…ABSTRACT The Barra Velha Formation and other Aptian pre‐salt deposits record the history of the proto‐Atlantic basin and the rifting of Gondwana. Studies have…”
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Diagenetic controls on the isotopic composition of carbonate‐associated sulphate in the Permian Capitan Reef Complex, West Texas by Present, Theodore M., Gutierrez, Melissa, Paris, Guillaume, Kerans, Charles, Grotzinger, John P., Adkins, Jess F., Tosca, Nicholas

“…Late Palaeozoic‐age strata from the Capitan Reef in west Texas show facies‐dependent heterogeneity in the sulphur isotopic composition of carbonate‐associated…”
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Active ooid growth driven by sediment transport in a high-energy shoal, Little Ambergris Cay, Turks and Caicos Islands by Trower, Elizabeth J, Cantine, Marjorie D, Gomes, Maya L, Grotzinger, John P, Knoll, Andrew H, Lamb, Michael P, Lingappa, Usha, O'Reilly, Shane S, Present, Theodore M, Stein, Nathan, Strauss, Justin V, Fischer, Woodward W

“…Ooids are a common component of carbonate successions of all ages and present significant potential as paleoenvironmental proxies, if the mechanisms that…”
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BIOSIGNATURE PRESERVATION AIDED BY ORGANIC-CATION INTERACTIONS IN PROTEROZOIC TIDAL ENVIRONMENTS by Moore, Kelsey R., Present, Theodore M., Pavia, Frank, Grotzinger, John P., Hollis, Joseph Razzell, Sharma, Sunanda, Flannery, David, Bosak, Tanja, Tuite, Michael, Knoll, Andrew H., Williford, Kenneth

“…The preservation of organic biosignatures during the Proterozoic Eon required specific taphonomic windows that could entomb organic matter to preserve…”
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Deposition of sulfate aerosols with positive Δ33S in the Neoarchean by Paris, Guillaume, Fischer, Woodward W., Johnson, Jena E., Webb, Samuel M., Present, Theodore M., Sessions, Alex L., Adkins, Jess F.

“…Anomalous sulfur isotope compositions present in Archean rocks have been intensely scrutinized over the last 20 years because they record key aspects of…”
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Geomorphic and environmental controls on microbial mat fabrics on Little Ambergris Cay, Turks and Caicos Islands by Stein, Nathaniel T., Grotzinger, John P., Quinn, Daven P., Lingappa, Usha F., Present, Theodore M., Trower, Elizabeth J., Gomes, Maya L., Orzechowski, Emily, Cantine, Marjorie, Metcalfe, Kyle S., Fischer, Woodward W., Ehlmann, Bethany L., Strauss, Justin V., Knoll, Andrew H.

“…To interpret microbially influenced paleoenvironments in the sedimentary record, it is crucial to understand what processes control the development of…”
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Early impacts of climate change on a coastal marine microbial mat ecosystem by Lingappa, Usha F, Stein, Nathaniel T, Metcalfe, Kyle S, Present, Theodore M, Orphan, Victoria J, Grotzinger, John P, Knoll, Andrew H, Trower, Elizabeth J, Gomes, Maya L, Fischer, Woodward W

“…Among the earliest consequences of climate change are extreme weather and rising sea levels-two challenges to which coastal environments are particularly…”
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Tools for uranium characterization in carbonate samples: case studies of natural U–Pb geochronology reference materials by Rasbury, E. Troy, Present, Theodore M., Northrup, Paul, Tappero, Ryan V., Lanzirotti, Antonio, Cole, Jennifer M., Wooton, Kathleen M., Hatton, Kevin

“…Laser ablation U–Pb analyses of carbonate (LAcarb) samples has greatly expanded the potential for U–Pb dating to a variety of carbonate-producing settings…”
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Sulfur isotopes in rivers: Insights into global weathering budgets, pyrite oxidation, and the modern sulfur cycle by Burke, Andrea, Present, Theodore M., Paris, Guillaume, Rae, Emily C.M., Sandilands, Brodie H., Gaillardet, Jérôme, Peucker-Ehrenbrink, Bernhard, Fischer, Woodward W., McClelland, James W., Spencer, Robert G.M., Voss, Britta M., Adkins, Jess F.

“…The biogeochemical sulfur cycle is intimately linked to the cycles of carbon, iron, and oxygen, and plays an important role in global climate via weathering…”
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Carbonate associated sulfate (CAS) δ34S heterogeneity across the End-Permian Mass Extinction in South China by Johnson, Daniel L., Present, Theodore M., Li, Menghan, Shen, Yanan, Adkins, Jess F.

“…•New carbonate associated sulfate (CAS) δ34S data across the end-Permian extinction.•CAS δ34S at South China localities varies by up to 20‰ within single hand…”
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Nondestructive geochemical characterization of fossil hominin taphonomy and burial history by Present, Theodore M., Niespolo, Elizabeth M., Clarke, Catherine E., Behrensmeyer, Anna K., Leakey, Louise N., Leakey, Meave G., Mongle, Carrie, Du Plessis, Anton, Northrup, Paul, Tappero, Ryan V., Yang, Deming, Rasbury, E. Troy, Grine, Fredrick E.

“…To date, only three Homo habilis specimens have been discovered that have associated craniodental and postcranial elements, providing a limited fossil record…”
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Nondestructive geochemical characterization of fossil hominin taphonomy and burial history by Present, Theodore M., Niespolo, Elizabeth M., Clarke, Catherine E., Behrensmeyer, Anna K., Leakey, Louise N., Leakey, Meave G., Mongle, Carrie, Du Plessis, Anton, Northrup, Paul, Tappero, Ryan V., Yang, Deming, Rasbury, E. Troy, Grine, Fredrick E.

“…To date, only three Homo habilis specimens have been discovered that have associated craniodental and postcranial elements, providing a limited fossil record…”
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Early diagenetic constraints on Permian seawater chemistry from the Capitan Reef by Bryant, Roger N., Present, Theodore M., Ahm, Anne-Sofie C., McClelland, Harry-Luke O., Razionale, Dan, Blättler, Clara L.

“…The Capitan Reef Complex in West Texas is famous for its high prevalence of early marine cements, unusual for a Phanerozoic platform, leading some to suggest…”
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Microbial Activity and Neomorphism Influence the Composition and Microfabric of Ooids From Great Salt Lake, UT by Lincoln, Tyler A., Webb, Samuel M., Present, Theodore M., Magyar, John S., Trower, Elizabeth J.

“…The sediment along the shorelines of Great Salt Lake (GSL), Utah is dominated by ooids, concentrically-coated carbonate sand grains. Two characteristics…”
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"Enriching Lives within Sedimentary Geology": Actionable Recommendations for Making SEPM a Diverse, Equitable, and Inclusive Society for All Sedimentary Geologists by Fernandes, Anjali M., Abeyta, Antoinette, Mahon, Robert C., Martindale, Rowan, Bergmann, Kristin D., Jackson, Christopher, Present, Theodore M., Reano, Darryl, Swanson, Travis, Butler, Kristina, Brisson, Sarah, Johnson, Cari, Mohrig, David, Blum, Michael D.

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