Search Results - "Ufnar, David F"

Development of a Swine-Specific Fecal Pollution Marker Based on Host Differences in Methanogen mcrA Genes by Ufnar, Jennifer A, Ufnar, David F, Wang, Shiao Y, Ellender, R.D

“…The goal of this study was to evaluate methanogen diversity in animal hosts to develop a swine-specific archaeal molecular marker for fecal source tracking in…”
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Methanobrevibacter ruminantium as an Indicator of Domesticated-Ruminant Fecal Pollution in Surface Waters by Ufnar, Jennifer A, Wang, Shiao Y, Ufnar, David F, Ellender, R.D

“…A PCR-based assay (Mrnif) targeting the nifH gene of Methanobrevibacter ruminantium was developed to detect fecal pollution from domesticated ruminants in…”
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Clay coatings from a modern soil chronosequence: A tool for estimating the relative age of well-drained paleosols by Ufnar, David F.

“…Blue light optically stimulated luminescence (OSL) dates obtained from upland and terrace soil profiles in southeastern Mississippi have been used to generate…”
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Reconstructing a Mid-Cretaceous landscape from paleosols in Western Canada by Ufnar, David F, González, Luis A, Ludvigson, Greg A, Brenner, Robert L, Witzke, Brian J, Leckie, Dale

“…The Albian Stage of the mid-Cretaceous was a time of equable climate conditions with high sea levels and broad shallow epeiric seas that may have had a…”
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Preservation Potential of Ultrabasic Volcanic Sand in an Arid Intracontinental Setting: Will the Hopi Buttes Maar-diatreme Field be Preserved in the Rock Record? by David F. Ufnar (1 ), Douglas P. Sm

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Assessing pedogenic calcite stable-isotope values: Can positive linear covariant trends be used to quantify palaeo-evaporation rates? by Ufnar, David F., Gröcke, Darren R., Beddows, Patricia A.

“…Palaeoclimate models suggest enhanced evaporation rates in subtropical regions (15–30° latitude) during greenhouse-world conditions, however, there are no…”
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Clay coatings from a modem soil chronosequence : A tool for estimating the relative age of well-drained paleosols by UFHAR, David F

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Precipitation rates and atmospheric heat transport during the Cenomanian greenhouse warming in North America: Estimates from a stable isotope mass-balance model by Ufnar, David F., Ludvigson, Greg A., González, Luis, Gröcke, Darren R.

“…Stable isotope mass-balance modeling results of meteoric δ 18O values from the Cenomanian Stage of the Cretaceous Western Interior Basin (KWIB) suggest that…”
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Early-Cenomanian terrestrial facies and paleoclimate records of the Lower Tuscaloosa Formation, southwestern Mississippi by Ufnar, David

“…Sphaerosiderite oxygen isotope values from the Early Cenomanian Lower Tuscaloosa Formation, or LTF, extend a mid-Cretaceous meteoric 18O latitudinal gradient…”
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The mid-Cretaceous water bearer: isotope mass balance quantification of the Albian hydrologic cycle by Ufnar, David F., A. González, Luis, Ludvigson, Greg A., Brenner, Robert L., Witzke, Brian J.

“…A latitudinal gradient in meteoric δ18O compositions compiled from paleosol sphaerosiderites throughout the Cretaceous Western Interior Basin (KWIB) (34–75°N…”
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Diagenetic overprinting of the sphaerosiderite palaeoclimate proxy: are records of pedogenic groundwater δ18O values preserved? by Ufnar, David F., González, Luis A., Ludvigson, Greg A., Brenner, Robert L., Witzke, Brian J.

“…Meteoric sphaerosiderite lines (MSLs), defined by invariant δ18O and variable δ13C values, are obtained from ancient wetland palaeosol sphaerosiderites…”
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Diagenetic overprinting of the sphaerosiderite palaeoclimate proxy: are records of pedogenic groundwater δ 18 O values preserved? by Ufnar, David F., González, Luis A., Ludvigson, Greg A., Brenner, Robert L., Witzke, Brian J.

“…Abstract Meteoric sphaerosiderite lines (MSLs), defined by invariant δ 18 O and variable δ 13 C values, are obtained from ancient wetland palaeosol…”
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Stratigraphic implications of meteoric sphaerosiderite δ18O values in Paleosols of the Cretaceous (Albian) Boulder Creek Formation, NE British Columbia foothills, Canada by Ufnar, David F, Gonzalez, Luis A, Ludvigson, Greg A, Brenner, Robert L, Witzke, Brian J

“…The MD 80-08 coal exploration core from the Albian Boulder Creek Formation of northeastern British Columbia contains 90 m of alluvial strata that underwent…”
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Aggradation of gravels in tidally influenced fluvial systems: upper Albian (Lower Cretaceous) on the cratonic margin of the North American Western Interior foreland basin by Brenner, Robert L., Ludvigson, Gregory A., Witzke, Brian L., Phillips, Preston Lee, White, Timothy S., Ufnar, David F., González, Luis A, Joeckel, R.Matthew, Goettemoeller, Adrian, Shirk, Benjamin R.

“…Alluvial conglomerates were widely distributed around the margin of the Early Cretaceous North American Cretaceous Western Interior Seaway (KWIS)…”
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