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Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger 2017 University of South Florida

Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger

Graduate Theses and Dissertations

The development of an accurate and precise geochronology is imperative to understanding archives containing information about Earth’s past. Unable to date all intervals of an archive, researchers use methods of interpolation to approximate age between dates. Sections of the radiocarbon calibration curve can induce larger chronological uncertainty independent of instrumental precision, meaning even a precise date may carry inflated error in its calibration to a calendar age. Methods of interpolation range from step-wise linear regression to, most recently, Bayesian statistical models. These employ prior knowledge of accumulation rate to provide a more informed interpolation between neighboring dates. This study ...


Characterizing The Evolution Of Slab Inputs In The Earliest Stages Of Subduction: Preliminary Evidence From The Fluid-Mobile Element (B, Cs, As, Li) Systematics Of Izu-Bonin Boninitic Glasses Recovered During Iodp Expedition 352, Keir Aavon Sanatan 2017 University of South Florida

Characterizing The Evolution Of Slab Inputs In The Earliest Stages Of Subduction: Preliminary Evidence From The Fluid-Mobile Element (B, Cs, As, Li) Systematics Of Izu-Bonin Boninitic Glasses Recovered During Iodp Expedition 352, Keir Aavon Sanatan

Graduate Theses and Dissertations

Fluid-mobile elements (FMEs) such as B, Cs, As, Li and Tl can mobilize readily under low P-T conditions (0.2-0.5 GPa). This makes them effective geochemical tracers that can be used as a way of tracking fluid-rock exchanges at the shallow depths encountered in the earliest stages of subduction.

The Izu-Bonin-Mariana (IBM) subduction system is unique in that it preserves a record of the sequences produced from the onset of subduction through the development of arc magmatism. International Ocean Discovery Program (IODP) Expedition 352 recovered >800m of boninite core material from the earliest IBM magmatic events.

Select boninitic glasses ...


Cu-Pd Mineralization And Exploration Geochemistry Of The Eastern Gabbro, Coldwell Alkaline Complex, On, Canada, Yonghua Cao 2017 The University of Western Ontario

Cu-Pd Mineralization And Exploration Geochemistry Of The Eastern Gabbro, Coldwell Alkaline Complex, On, Canada, Yonghua Cao

Electronic Thesis and Dissertation Repository

The Eastern Gabbro forms the northern and eastern margin of the Coldwell Alkaline Complex. It contains three magma series: the barren meta-basalt, the Layered Series, and the Marathon Series which hosts all known PGE mineralization. The Marathon Series can be distinguished from other Series using the combination of portable X-ray fluorescence (pXRF) and benchtop scanning electron microscope (bSEM). Whole-rock Ba, Mg# (molar Mg/(Mg+Fe)*100), Zr and V/Ti values acquired from pXRF, and Mg#s of olivine and clinopyroxene, and anorthite content (molar Ca/(Ca+Na)*100) of plagioclase acquired from bSEM-EDS are key parameters. The Layered Series ...


Dependence Of The Martian Radiation Environment On Atmospheric Depth: Modeling And Measurement, Jingnan Guo, Tony C. Slaba, Cary Zeitlin, Robert F. Wimmer-Schweingruber, Francis F. Badavi, Eckart Böhm, Stephan Böttcher, David E. Brinza, Bent Ehresmann, Donald M. Hassler 2017 Old Dominion University

Dependence Of The Martian Radiation Environment On Atmospheric Depth: Modeling And Measurement, Jingnan Guo, Tony C. Slaba, Cary Zeitlin, Robert F. Wimmer-Schweingruber, Francis F. Badavi, Eckart Böhm, Stephan Böttcher, David E. Brinza, Bent Ehresmann, Donald M. Hassler

Physics Faculty Publications

The energetic particle environment on the Martian surface is influenced by solar and heliospheric modulation and changes in the local atmospheric pressure (or column depth). The Radiation Assessment Detector (RAD) on board the Mars Science Laboratory rover Curiosity on the surface of Mars has been measuring this effect for over four Earth years (about two Martian years). The anticorrelation between the recorded surface Galactic Cosmic Ray-induced dose rates and pressure changes has been investigated by Rafkin et al. (2014) and the long-term solar modulation has also been empirically analyzed and modeled by Guo et al. (2015). This paper employs the ...


Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti 2017 University of Bologna

Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti

International Journal of Speleology

Over the past 15 years several expeditions by French, American and especially Italian cavers have unveiled over 50 caves in the Cordillera de la Sal (Atacama Desert, Northern Chile). Many of these caves contain a variety of speleothems and minerals, some of which have rarely been observed within karst systems. Most of the secondary deposits in these caves are composed of halite, but also other halide, carbonate, sulphate, nitrate, phosphate, and silicate minerals have been found. Among the sixteen cave mineral species recognized, atacamite, darapskite, blödite, leonite, anhydrite, and especially antarcticite are worth mentioning. In one of the samples an ...


Petrographical And Geochemical Changes In Bosnian Stalagmites And Their Palaeo-Environmental Significance, Veronica Chiarini, Isabelle Couchoud, Russell Drysdale, Petra Bajo, Simone Milanolo, Silvia Frisia, Alan Greig, John Hellstrom, Jo De Waele 2017 University of Bologna

Petrographical And Geochemical Changes In Bosnian Stalagmites And Their Palaeo-Environmental Significance, Veronica Chiarini, Isabelle Couchoud, Russell Drysdale, Petra Bajo, Simone Milanolo, Silvia Frisia, Alan Greig, John Hellstrom, Jo De Waele

International Journal of Speleology

Detailed petrographic observations have been coupled with trace element and δ13C - δ18O analyses in order to investigate their dynamics in two Holocene Bosnian speleothems. The potential of this multiproxy approach in providing a means to extract palaeo-environmental information from stalagmites whose stable isotope signals are noisy and without obvious trends has been tested. The studied stalagmites are mostly characterized by columnar microcrystalline fabric. At the sub-millimetre scale of lamination, different microcrystalline columnar sub-types (open and closed) have been detected and classified on the basis of the observed porosity and the crystallite size. The presence of variations ...


Eruption Record And Aspects Of Magma Genesis And Evolution For Volcanoes Of The Southernmost Andean Southern Volcanic Zone, Chile, Derek James Weller 2017 University of Colorado at Boulder

Eruption Record And Aspects Of Magma Genesis And Evolution For Volcanoes Of The Southernmost Andean Southern Volcanic Zone, Chile, Derek James Weller

Geological Sciences Graduate Theses & Dissertations

Sediment cores from twelve lakes located to the east of the volcanic front of the southernmost portion of the Andean Southern Volcanic Zone (SSVZ) preserve greater than 75 late Pleistocene to Holocene tephras derived from different explosive eruptions of volcanoes in this region. Correlation of the tephra deposits and source volcano identification are based on the stratigraphic position of the tephra within the cores, tephra lithostratigraphic data (deposit thickness, grain size) and petrochemistry. Only 7 of these tephra have been previously identified in outcrops, indicating the importance of lake cores for identifying smaller eruptions. The suggested source volcanoes for these ...


Geochemical And Mineralogical Analyses Of Cold Spring Deposits From Borup Fiord Pass, A Sulfur-Dominated Arctic Analog For Planetary Environments On Mars And Europa, Graham Elliot Lau 2017 University of Colorado at Boulder

Geochemical And Mineralogical Analyses Of Cold Spring Deposits From Borup Fiord Pass, A Sulfur-Dominated Arctic Analog For Planetary Environments On Mars And Europa, Graham Elliot Lau

Geological Sciences Graduate Theses & Dissertations

Sulfur is one of the most ubiquitous elements in the universe and one of those that is crucial for life, as we know it. This graduate dissertation presents the culmination of work conducted to better understand biological and geochemical processes related to sulfur cycling at a sulfur-dominated field site in the Canadian High Arctic. This site, situated in a valley called Borup Fiord Pass, provides a unique environment where sulfide-rich fluids emerge from a glacier and form large deposits of ice that become covered in elemental sulfur. The role of biology is compelling and yet challenging to define in each ...


Stable Isotope Investigation Of The Migratory Behavior Of Silverhaired Bats (Lasionycteris Noctivagans) In Eastern North America, Erin E. Fraser, Darin Brooks, Fred J. Longstaffe 2017 Memorial University of Newfoundland

Stable Isotope Investigation Of The Migratory Behavior Of Silverhaired Bats (Lasionycteris Noctivagans) In Eastern North America, Erin E. Fraser, Darin Brooks, Fred J. Longstaffe

Earth Sciences Publications

We investigated the migratory movements of silver-haired bats (Lasionycteris noctivagans) across the eastern extent of the species’ range. We conducted stable hydrogen isotope analysis of fur samples (δ2Hfur) from museum specimens collected across latitudes and at all times of the year. We first used these data to estimate the timing of fur replacement and to develop a model associating δ2Hfur with that of local precipitation (δ2Hprecip) at the location where fur replacement occurred. We then used this model to 1) identify individuals that had migrated across latitudes, and 2) investigate the ...


Origin Of Graphite In The Southwestern Grenville Province, Mehmet F. Taner, Cameron Drever, Chris Yakymhuk, Fred Longstaffe 2017 University of Waterloo

Origin Of Graphite In The Southwestern Grenville Province, Mehmet F. Taner, Cameron Drever, Chris Yakymhuk, Fred Longstaffe

Earth Sciences Publications

Two graphite deposits in the southwestern Grenville Province are investigated to evaluate the origin of graphitic carbon and to test if the graphite mineralization is syngenetic or epigenetic. Graphite mineralization in the Bissett Creek deposit is characterized by homogeneously distributed and disseminated graphite flakes (approximately 1 to 5 mm in size and 2 to 10 vol.%) within graphitic gneisses. The graphite flakes are intergrown with metamorphic minerals, most notably biotite. The Montpellier graphite showing in Qu´ebec contains graphite concentrations of up to 20 vol.%. In contrast to the disseminated and homogenously distributed graphite in the Bissett Creek deposit, graphite ...


Carbon Monoxide Stable Isotopes: Extraction Technique Development And Urban Atmospheric Analysis, Isaac Vimont 2017 University of Colorado at Boulder

Carbon Monoxide Stable Isotopes: Extraction Technique Development And Urban Atmospheric Analysis, Isaac Vimont

Geological Sciences Graduate Theses & Dissertations

We have developed an extraction system to analyze isotopes of carbon monoxide (CO). We then analyzed CO isotopes for two years at Indianapolis, IN, USA. These measurements were done at three towers, one of which measured incoming, background air into the city. We quantitatively removed the background signal and determined the urban CO mole fraction and isotopic enhancements. During the winter months, we constrained the isotopic signature and concluded that the majority of CO produced during the winter was produced by fossil fuel combustion. We found that the Indianapolis fossil fuel signature differed from that of studies done in Europe ...


Rock Magnetic Investigation Of The Michigan Basin Soils And Sediments Overlying The Oil-Bearing Silurian Pinnacle Reefs, Jake Tresnak 2017 Michigan Technological University

Rock Magnetic Investigation Of The Michigan Basin Soils And Sediments Overlying The Oil-Bearing Silurian Pinnacle Reefs, Jake Tresnak

Dissertations, Master's Theses and Master's Reports

A relationship between the hydrocarbon migration and magnetic properties of near-surface sediments was investigated from several hundreds of samples collected over the hydrocarbon-bearing Silurian pinnacle reef belt of the Michigan Basin. The collected samples were investigated using several rock magnetic methods and optical microscopy. The investigation has not revealed a straightforward relationship between the magnetic susceptibility and hydrocarbon reservoirs within the reef belt; both anomalously high and low susceptibility values were observed. The elevated values are associated with newly formed magnetite in the form of spheroidal grains produced by hydrocarbon-related diagenesis while the extremely low susceptibilities may reflect dissolution of ...


Mono Lake Data, Larry Benson 2017 U.S. Geological Survey

Mono Lake Data, Larry Benson

Data Sets for USGS Research

Mono Lake Basin Data\ Depth CalAge TIC TOTC TOC 13C 18O

Mono Lake short cores.xlsx 03.03.2014 19:59:44 0.06 xlsx

Depth PSV age 18O 13C

TIC for Wilson Crk Fm.xlsx 02.03.2014 16:07:10 0.03 xlsx

Ostracode 18O and TE data Wilson Crk Fm.xlsx 10.11.2017 17:43:18 0.12 xlsx

Depth, calendar age, TIC, TOTC, TOC, 13C, and 18O of Mono Lake short cores were reported in:

Benson, L., Linsley, B., Smoot, J., Mensing, S., Lund, S., Stine, S., and Sarna-Wojcicki, A., 2003, Influence of ...


Summer Lake Basin Data, Larry Benson 2017 U.S. Geological Survey

Summer Lake Basin Data, Larry Benson

Data Sets for USGS Research

Summer Lake Basin

Name Date modified Time modified Size MB Extension

Summer Lake Basin\

Depth PSV Age 13C 18O Summer Lake B&B core.xlsx 03.03.2014 16:51:12 0.03 xlsx

In the Summer Lake Basin folder:

Depth, PSV age, 18O, 13C data for Summer Lake core B&B are reported in:

Benson, L., Lund, S., Negrini, R., Linsley, B., and Zic, M., 2003, Response of North American Great Basin lakes to Dansgaard-Oeschger oscillations: Quaternary Science Reviews vol. 22, p. 2239-2251.

General Comment: In most cases an age model based on 14C analyses is ...


Reconstructed Discharge For Truckee River, Larry Benson 2017 U.S. Geological Survey

Reconstructed Discharge For Truckee River, Larry Benson

Data Sets for USGS Research

Reconstructed Discharge for Truckee River

Name Date modified Time modified Size MB Extension

Reconstructed Discharge Truckee R\ Reconstructed Discharge for Truckee River.xlsx 11.11.2017 22:40:52 0.02 xlsx

Reconstructed discharge of the Truckee River was made considering losses to evaporation in all upstream reservoirs and corrected for diversion from the Derby Dam to the Newlands area. This data was never previously published.

General Comment: In most cases an age model based on 14C analyses is not included with the data sets although ones were created for the original publications. Given the general problems with 14C ages ...


Walker Lake Basin Data, Larry Benson, Steve P. Lund 2017 U.S. Geological Survey

Walker Lake Basin Data, Larry Benson, Steve P. Lund

Data Sets for USGS Research

Walker Lake Basin Data

Name Date modified Time modified Size MB Extension

Walker Lake Core 84-8 isotope and age data.xls 27.01.2018 15:25:52 0.03 xls

Walker Lake core WL002 PSV age and chemical data.xlsx 09.02.2018 20:04:50 0.03 xlsx

In the Walker Lake Basin folder:

Depth, 14C age (not corrected for reservoir effect), 18O, 13C data for core 84-8 are reported in:

Benson, L.V., 1988, Preliminary paleolimnologic data for the Walker Lake subbasin, California and Nevada: U.S. Geological Survey Water-Resources Investigations Report 87-4258, 50p. Palaeogeography ...


Pyramid Lake Core Data, Larry Benson 2017 U.S. Geological Survey

Pyramid Lake Core Data, Larry Benson

Data Sets for USGS Research

Pyramid Lake Core Data

14C and calibrated ages for core PLC08-1.xlsx 01.03.2014 19:45:30 0.01 xlsx

14C and calibrated ages for core PLC92B.xlsx 04.03.2014 16:41:30 0.01 xlsx

14C and calibrated ages for core PLC97-3.xlsx 01.03.2014 19:50:48 0.01 xlsx

CalKa Depth TOC TIC 18O 13C for PLC97-1.xlsx 09.11.2017 20:51:22 0.04 xlsx

Depth 14CAge Corrected 14C AGE CAL Age PLC98-4.xlsx 15.11.2017 18:26:12 0.01 xlsx

Depth 180 13C TOTC TOC TIC porosity CYBP Box ...


Pyramid And Winnemucca Lake Basin Carbonate Data, Larry Benson 2017 U.S. Geological Survey

Pyramid And Winnemucca Lake Basin Carbonate Data, Larry Benson

Data Sets for USGS Research

In the Pyramid and Winnemucca lake basin carbonate data folder:

New unpublished and previously published 14C and calibrated ages for materials in the Winnemucca Caves are reported in the table and in the references listed below the table

14C and calibrated ages for Winnemucca Lake Basin carbonates are reported in:

Benson, L.V., Hattori, E.M., Southon, J., Aleck, B., 2013. Dating North America’s oldest petroglyphs, Winnemucca Lake subbasin, Nevada. Journal of Archaeological Science 40, 4466-4476.

Tufa 87Sr, 18O, and 13C data are reported in:

Benson, L.V., Smoot, J.P., Lund, S.P ...


Owens Lake Core Data, Larry Benson 2017 U.S. Geological Survey

Owens Lake Core Data, Larry Benson

Data Sets for USGS Research

In the Owens Lake core data folder:

14C ages for cores OL84 and OL90 were reported in:

Benson, L.V., Burdett, J.W., Kashgarian, M., Lund, S.P., Phillips, F.M., and Rye, R.O., 1996, Climatic and hydrologic Oscillations in the Owens Lake basin and adjacent Sierra Nevada, California: Science, vol. 274, p. 746-749.

Benson, L.V., 1999, Records of millennial-scale climate change from the Great Basin of the Western United States: In Clark, P., Webb, R., Keigwin, L., eds., Mechanisms of Global Climate Change at Millennial Time Scales, American Geophysical Union Monograph 112, p. 203-225.

Benson, L ...


Great Basin Surface Water And Precipitation Isotope Data, Larry Benson 2017 U.S. Geological Survey

Great Basin Surface Water And Precipitation Isotope Data, Larry Benson

Data Sets for USGS Research

In the Great Basin Surface Water and Precipitation Isotope Data folder:

Farad, Nixon, and Pyramid Lake 18O data were reported in:

Benson, L.V., 1994, Stable isotopes of oxygen and hydrogen in the Truckee River-Pyramid Lake surface-water system. 1. Data analysis and extraction of paleoclimatic information: Limnology and Oceanography, vol. 39, p. 344-355. https://digitalcommons.unl.edu/usgsstaffpub/1015

Spring chemistry around Pyramid Lake data were reported in:

Benson, L.V., 1994, Carbonate deposition, Pyramid Lake subbasin, Nevada: 1. Sequence of formation and elevational distribution of carbonate deposits (tufas): Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 109, p. 55-87.

Benson, L.V., Kashgarian ...


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