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Articles 61 - 90 of 521

Full-Text Articles in Earth Sciences

Science And Curation Considerations For The Design Of A Mars Sample Return (Msr) Sample Receiving Facility (Srf), Brandi L. Carrier, David W. Beaty, Aurore Hutzler, Alvin L. Smith, Gerhard Kminek, Michael A. Meyer, Timothy Haltigin, Lindsey E. Hays, Carl B. Agee, Henner Busemann, Barabara Cavalazzi, Charles S. Cocksell, Vinciane Debaille, Daniel P. Glavin, Monica M. Grady, Ernst Hauber, Bernard Marty, Francis M., Lisa M. Pratt, Aaron B. Regberg, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Taiit, Nocholas J. Tosca, Arya Urdry, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Frances Westall, Maria-Paz Zorzano Jun 2022

Science And Curation Considerations For The Design Of A Mars Sample Return (Msr) Sample Receiving Facility (Srf), Brandi L. Carrier, David W. Beaty, Aurore Hutzler, Alvin L. Smith, Gerhard Kminek, Michael A. Meyer, Timothy Haltigin, Lindsey E. Hays, Carl B. Agee, Henner Busemann, Barabara Cavalazzi, Charles S. Cocksell, Vinciane Debaille, Daniel P. Glavin, Monica M. Grady, Ernst Hauber, Bernard Marty, Francis M., Lisa M. Pratt, Aaron B. Regberg, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Taiit, Nocholas J. Tosca, Arya Urdry, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

The most important single element of the “ground system” portion of a Mars Sample Return (MSR) Campaign is a facility referred to as the Sample Receiving Facility (SRF), which would need to be designed and equipped to receive the returned spacecraft, extract and open the sealed sample container, extract the samples from the sample tubes, and implement a set of evaluations and analyses of the samples. One of the main findings of the first MSR Sample Planning Group (MSPG, 2019a) states that “The scientific community, for reasons of scientific quality, cost, and timeliness, strongly prefers that as many sample-related investigations …

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The Scientific Importance Of Returning Airfall Dust As A Part Of Mars Sample Return (Msr), Monica M. Grady, Roger E. Summons, Timothy D. Swindle, Frances Westall, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agee, Henner Busemann, Barabara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Daniel P. Galvin, Ernst Hauber, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Lisa M. Pratt, Aaron B, Regberg, Alvin L. Smith, Caroline L. Smith, Kimberly T. Tait, Nicholas J. Tosca, Arya Udry, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Maria-Paz Zorzano Jun 2022

The Scientific Importance Of Returning Airfall Dust As A Part Of Mars Sample Return (Msr), Monica M. Grady, Roger E. Summons, Timothy D. Swindle, Frances Westall, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agee, Henner Busemann, Barabara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Daniel P. Galvin, Ernst Hauber, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Lisa M. Pratt, Aaron B, Regberg, Alvin L. Smith, Caroline L. Smith, Kimberly T. Tait, Nicholas J. Tosca, Arya Udry, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Maria-Paz Zorzano

Geoscience Faculty Research

Dust transported in the martian atmosphere is of intrinsic scientific interest and has relevance for the planning of human missions in the future. The MSR Campaign, as currently designed, presents an important opportunity to return serendipitous, airfall dust. The tubes containing samples collected by the Perseverance rover would be placed in cache depots on the martian surface perhaps as early as 2023–24 for recovery by a subsequent mission no earlier than 2028–29, and possibly as late as 2030–31. Thus, the sample tube surfaces could passively collect dust for multiple years. This dust is deemed to be exceptionally valuable as it …

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Time-Sensitive Aspects Of Mars Sample Return (Msr) Science, Nicholas J. Tosca, Carl B. Agee, Charles S. Cockell, Daniel P. Glavin, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Aaron B. Regberg, Michael A. Velbel, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Henner Baumann, Barbara Cavalazzi, Vinviane Debaille, Monica M. Grady, Ernst Hauber, Lisa M. Pratt, Alvin L. Smith, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Arya Udry, Tomohiro Usui, Meenakshi Wadhwa, Frances Westall, Maria-Paz Zorzano Jun 2022

Time-Sensitive Aspects Of Mars Sample Return (Msr) Science, Nicholas J. Tosca, Carl B. Agee, Charles S. Cockell, Daniel P. Glavin, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Aaron B. Regberg, Michael A. Velbel, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Henner Baumann, Barbara Cavalazzi, Vinviane Debaille, Monica M. Grady, Ernst Hauber, Lisa M. Pratt, Alvin L. Smith, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Arya Udry, Tomohiro Usui, Meenakshi Wadhwa, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

Samples returned from Mars would be placed under quarantine at a Sample Receiving Facility (SRF) until they are considered safe to release to other laboratories for further study. The process of determining whether samples are safe for release, which may involve detailed analysis and/or sterilization, is expected to take several months. However, the process of breaking the sample tube seal and extracting the headspace gas will perturb local equilibrium conditions between gas and rock and set in motion irreversible processes that proceed as a function of time. Unless these time-sensitive processes are understood, planned for, and/or monitored during the quarantine …

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Planning Implications Related To Sterilization-Sensitive Science Investigations Associated With Mars Sample Return (Msr), Michael A. Velbel, Charles S. Cockell, Daniel P. Glavin, Bernard Marty, Aaron B. Regberg, Alvin L. Smith, Nicholas J. Tosca, Meenakshi Wadhwa, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi Lee Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agee, Henner Busemann, Barbara Cavalazzi, Vinciane Debaille, Monica M. Grady, Ernst Hauber, Aurore Hutzler, Francis M. Mccubbin, Lisa M. Pratt, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Arya Udry, Tomohiro Usui, Frances Westall, Maria-Paz Zorzano Jun 2022

Planning Implications Related To Sterilization-Sensitive Science Investigations Associated With Mars Sample Return (Msr), Michael A. Velbel, Charles S. Cockell, Daniel P. Glavin, Bernard Marty, Aaron B. Regberg, Alvin L. Smith, Nicholas J. Tosca, Meenakshi Wadhwa, Gerhard Kminek, Michael A. Meyer, David W. Beaty, Brandi Lee Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agee, Henner Busemann, Barbara Cavalazzi, Vinciane Debaille, Monica M. Grady, Ernst Hauber, Aurore Hutzler, Francis M. Mccubbin, Lisa M. Pratt, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Arya Udry, Tomohiro Usui, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

The NASA/ESA Mars Sample Return (MSR) Campaign seeks to establish whether life on Mars existed where and when environmental conditions allowed. Laboratory measurements on the returned samples are useful if what is measured is evidence of phenomena on Mars rather than of the effects of sterilization conditions. This report establishes that there are categories of measurements that can be fruitful despite sample sterilization and other categories that cannot. Sterilization kills living microorganisms and inactivates complex biological structures by breaking chemical bonds. Sterilization has similar effects on chemical bonds in non-biological compounds, including abiotic or pre-biotic reduced carbon compounds, hydrous minerals, …

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Final Report Of The Mars Sample Return Science Planning Group 2 (Mspg2), Michael A. Meyer, Gerhard Kminek, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agree, Henner Busemann, Barbara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Daniel P. Glavin, Monica M. Grady, Ernst Hauber, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Lisa M. Pratt, Aaron B. Regberg, Alvin L. Smith, Carolina L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Nicholas J. Tosca, Arya Udry, Tomohiro Usui, Michael A. Velbel, Meensakshi Wadhwa, Frances Westall, Maria-Paz Zorzano Jun 2022

Final Report Of The Mars Sample Return Science Planning Group 2 (Mspg2), Michael A. Meyer, Gerhard Kminek, David W. Beaty, Brandi L. Carrier, Timothy Haltigin, Lindsay E. Hays, Carl B. Agree, Henner Busemann, Barbara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Daniel P. Glavin, Monica M. Grady, Ernst Hauber, Aurore Hutzler, Bernard Marty, Francis M. Mccubbin, Lisa M. Pratt, Aaron B. Regberg, Alvin L. Smith, Carolina L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Nicholas J. Tosca, Arya Udry, Tomohiro Usui, Michael A. Velbel, Meensakshi Wadhwa, Frances Westall, Maria-Paz Zorzano

Geoscience Faculty Research

The Mars Sample Return (MSR) Campaign must meet a series of scientific and technical achievements to be successful. While the respective engineering responsibilities to retrieve the samples have been formalized through a Memorandum of Understanding between ESA and NASA, the roles and responsibilities of the scientific elements have yet to be fully defined. In April 2020, ESA and NASA jointly chartered the MSR Science Planning Group 2 (MSPG2) to build upon previous planning efforts in defining 1) an end-to-end MSR Science Program and 2) needed functionalities and design requirements for an MSR Sample Receiving Facility (SRF). The challenges for the …

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Rationale And Proposed Design For A Mars Sample Return (Msr) Science Program, Timothy Haltigin, Ernst Hauber, Gerhard Kminek, Michael A. Meyer, Carl B. Agee, Henner Busemann, Brandi L. Carrier, Daniel P. Glavin, Lindsay E. Hays, Bernard Marty, Lisa M. Pratt, Arya Udry, Maria-Paz Zorzano, David W. Beaty, Barbara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Monica M. Grady, Aurore Hutzler, Francis M. Mccubbin, Aaron B. Regberg, Alvin L. Smith, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Nicholas J. Tosca, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Frances Westall Jun 2022

Rationale And Proposed Design For A Mars Sample Return (Msr) Science Program, Timothy Haltigin, Ernst Hauber, Gerhard Kminek, Michael A. Meyer, Carl B. Agee, Henner Busemann, Brandi L. Carrier, Daniel P. Glavin, Lindsay E. Hays, Bernard Marty, Lisa M. Pratt, Arya Udry, Maria-Paz Zorzano, David W. Beaty, Barbara Cavalazzi, Charles S. Cockell, Vinciane Debaille, Monica M. Grady, Aurore Hutzler, Francis M. Mccubbin, Aaron B. Regberg, Alvin L. Smith, Caroline L. Smith, Roger E. Summons, Timothy D. Swindle, Kimberly T. Tait, Nicholas J. Tosca, Tomohiro Usui, Michael A. Velbel, Meenakshi Wadhwa, Frances Westall

Geoscience Faculty Research

The Mars Sample Return (MSR) Campaign represents one of the most ambitious scientific endeavors ever undertaken. Analyses of the martian samples would offer unique science benefits that cannot be attained through orbital or landed missions that rely only on remote sensing and in situ measurements, respectively. As currently designed, the MSR Campaign comprises a number of scientific, technical, and programmatic bodies and relationships, captured in a series of existing and anticipated documents. Ensuring that all required scientific activities are properly designed, managed, and executed would require significant planning and coordination. Because there are multiple scientific elements that would need to …

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Climatic Backdrop For Pueblo Cultural Development In The Southwestern United States, Victor J. Polyak, Yemane Asmerom, Matthew S. Lachniet May 2022

Climatic Backdrop For Pueblo Cultural Development In The Southwestern United States, Victor J. Polyak, Yemane Asmerom, Matthew S. Lachniet

Geoscience Faculty Research

While climatic triggers for collapse and population migrations of ancestral Pueblo communities have been proposed, little is known about the overall climatic backdrop for the entire pre-Hispanic Pueblo period (ca. 1300 to 460 B2K). Here, we report data from stalagmite HC-1, from Hidden Cave, Guadalupe Mountains, New Mexico, covering the past 3400 years, showing an interval of increased frequency of droughts from 1260 to 370 yr B2K that is coeval with the entire pre-Hispanic Pueblo period. Our record suggests that this puebloan Late Holocene climatic interval was the most arid and highly variable climatic period of the last 3400 years. …

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Quantification Of Organic Carbon Sequestered By Biogenic Iron Sulfide Minerals In Long-Term Anoxic Laboratory Incubations, Nader Nabeh, Cheyenne Brokaw, Aude Picard Apr 2022

Quantification Of Organic Carbon Sequestered By Biogenic Iron Sulfide Minerals In Long-Term Anoxic Laboratory Incubations, Nader Nabeh, Cheyenne Brokaw, Aude Picard

Life Sciences Faculty Research

Organic carbon sequestration in sedimentary environments controls oxygen and carbon dioxide concentrations in the atmosphere. While minerals play an important role in the preservation of organic carbon, there is a lack of understanding about the formation and stability of organo-mineral interactions in anoxic environments, especially those involving authigenic iron sulfide minerals. In this study, we quantified organic carbon and nitrogen sequestered in biogenic iron sulfide minerals co-precipitated with sulfate-reducing bacteria (SRB) in freshwater and marine conditions in long-term laboratory experiments. The amounts of C and N associated with biogenic iron sulfide minerals increased with increasing cell biomass concentrations available in …

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Systematic Paleontology, Acritarch Biostratigraphy, And Δ13c Chemostratigraphy Of The Early Ediacaran Krol A Formation, Lesser Himalaya, Northern India, Shuhai Xiao, Ganqing Jiang, Qin Ye, Qing Ouyang, Dhiraj M. Banerjee, Birendra P. Singh, A. D. Muscente, Chuanming Zhou, Nigel C. Hughes Apr 2022

Systematic Paleontology, Acritarch Biostratigraphy, And Δ13c Chemostratigraphy Of The Early Ediacaran Krol A Formation, Lesser Himalaya, Northern India, Shuhai Xiao, Ganqing Jiang, Qin Ye, Qing Ouyang, Dhiraj M. Banerjee, Birendra P. Singh, A. D. Muscente, Chuanming Zhou, Nigel C. Hughes

Geoscience Faculty Research

Acritarch biostratigraphic and δ13C chemostratigraphic data from the Krol A Formation in the Solan area (Lesser Himalaya, northern India) are integrated to aid inter-basinal correlation of early–middle Ediacaran strata. We identified a prominent negative δ13C excursion (likely equivalent to EN2 in the lower Doushantuo Formation in the Yangtze Gorges area of South China), over a dozen species of acanthomorphs (including two new species—Cavaspina tiwariae Xiao n. sp., Dictyotidium grazhdankinii Xiao n. sp.), and numerous other microfossils from an interval in the Krol A Formation. Most microfossil taxa from the Krol A and the underlying Infra-Krol formations are also present in …

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In Situ Recording Of Mars Soundscape, S. Maurice, B. Chide, N. Murdoch, R. D. Lorenz, D. Mimoun, R. C. Wiens, Arya Udry, The Supercam Team Apr 2022

In Situ Recording Of Mars Soundscape, S. Maurice, B. Chide, N. Murdoch, R. D. Lorenz, D. Mimoun, R. C. Wiens, Arya Udry, The Supercam Team

Geoscience Faculty Research

Before the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (1) atmospheric turbulence changes at centimetre scales or smaller at the point where molecular viscosity converts kinetic energy into heat1, (2) the speed of sound varies at the surface with frequency2,3 and (3) high-frequency waves are strongly attenuated with distance in CO2 (refs. 2,3,4). However, theoretical models were uncertain because of a lack of experimental data at low pressure and the difficulty to characterize turbulence or attenuation in a closed environment. Here, using Perseverance microphone recordings, we present the first characterization of the acoustic environment …

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Arsenic Mineral In Volcanic Tuff, A Source Of Arsenic Anomaly In Groundwater: City Of Chihuahua, Mexico, Minghua Ren, José A. Rodríguez-Pineda, Philip Goodell Feb 2022

Arsenic Mineral In Volcanic Tuff, A Source Of Arsenic Anomaly In Groundwater: City Of Chihuahua, Mexico, Minghua Ren, José A. Rodríguez-Pineda, Philip Goodell

Geoscience Faculty Research

Arsenic is a naturally occurring trace element that causes many health effects when present in drinking water. Elevated arsenic concentrations in water are often attributed to nearby felsic volcanic sequences; however, the specific rock units to which the groundwater anomalies can be accredited are rarely identified. The groundwater from wells around the city of Chihuahua, Mexico, contains high arsenic content. Arsenic in groundwater increases toward the base rock containing Tertiary volcanic rocks. Through detailed scanning electron microscope (SEM) and electron microprobe (EMP) work, arsenic minerals are identified in the cavities of the Tertiary volcanic tuff from the northeast part of …

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Numerical Modeling Of Mineralizing Processes During The Formation Of The Yangzhuang Kiruna-Type Iron Deposit, Middle And Lower Yangtze River Metallogenic Belt, China: Implications For The Genesis And Longevity Of Kiruna-Type Iron Oxide-Apatite Systems, Xunyu Hu, Simon Jowitt, Feng Yuan, Guangxian Liu, Jinhui Luo, Yuhua Chen, Hui Yang, Keyue Ren, Yongguo Yang Dec 2021

Numerical Modeling Of Mineralizing Processes During The Formation Of The Yangzhuang Kiruna-Type Iron Deposit, Middle And Lower Yangtze River Metallogenic Belt, China: Implications For The Genesis And Longevity Of Kiruna-Type Iron Oxide-Apatite Systems, Xunyu Hu, Simon Jowitt, Feng Yuan, Guangxian Liu, Jinhui Luo, Yuhua Chen, Hui Yang, Keyue Ren, Yongguo Yang

Geoscience Faculty Research

The Yangzhuang iron deposit is a Kiruna-type iron oxide-apatite (IOA) deposit within the Ningwu mining district of the Middle and Lower Yangtze River Metallogenic Belt (MLYRMB), China. This study applies a numerical modeling approach to identify the key processes associated with the formation of the deposit that cannot be easily identified using traditional analytical approaches, including the duration of the mineralizing process and the genesis of iron orebodies within intrusions associated with the deposit. This approach highlights the practical value of numerical modeling in quantitatively analyzing mineralizing processes during the formation of mineral deposits and assesses how these methods can …

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Antagonistic Role Of Aqueous Complexation In The Solvent Extraction And Separation Of Rare Earth Ions, Pan Sun, Erik A. Binter, Zhu Liang, M. Alex Brown, Artem V. Gelis, Ilan Benjamin, Mrinal K. Bera, Binhua Lin, Wei Bu, Mark L. Schlossman Nov 2021

Antagonistic Role Of Aqueous Complexation In The Solvent Extraction And Separation Of Rare Earth Ions, Pan Sun, Erik A. Binter, Zhu Liang, M. Alex Brown, Artem V. Gelis, Ilan Benjamin, Mrinal K. Bera, Binhua Lin, Wei Bu, Mark L. Schlossman

Chemistry and Biochemistry Faculty Research

Solvent extraction is used widely for chemical separations and environmental remediation. Although the kinetics and efficiency of this process rely upon the formation of ion-extractant complexes, it has proven challenging to identify the location of ion-extractant complexation within the solution and its impact on the separation. Here, we use tensiometry and X-ray scattering to characterize the surface of aqueous solutions of lanthanide chlorides and the water-soluble extractant bis(2-ethylhexyl) phosphoric acid (HDEHP), in the absence of a coexisting organic solvent. These studies restrict ion-extractant interactions to the aqueous phase and its liquid-vapor interface, allowing us to explore the consequences that one …

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Initial Acoustoelastic Measurements In Olivine: Investigating The Effect Of Stress On P- And S-Wave Velocities, Taryn K. Traylor, Pamela C. Burnley, M. L. Whitaker Oct 2021

Initial Acoustoelastic Measurements In Olivine: Investigating The Effect Of Stress On P- And S-Wave Velocities, Taryn K. Traylor, Pamela C. Burnley, M. L. Whitaker

Geoscience Faculty Research

It is well known that elasticity is a key physical property in the determination of the structure and composition of the Earth and provides critical information for the interpretation of seismic data. This study investigates the stress-induced variation in elastic wave velocities, known as the acoustoelastic effect, in San Carlos olivine. A recently developed experimental ultrasonic acoustic system, the Directly Integrated Acoustic System Combined with Pressure Experiments (DIASCoPE), was used with the D-DIA multi-anvil apparatus to transmit ultrasonic sound waves and collect the reflections. We use the DIASCoPE to obtain longitudinal (P) and shear (S) elastic wave velocities from San …

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Shallow Rupture Propagation Of Pleistocene Earthquakes Along The Hurricane Fault, Ut, Revealed By Hematite (U-Th)/He Thermochronometry And Textures, Madison P. Taylor, Alexis K. Ault, Margaret L. Odlum, Dennis L. Newell Sep 2021

Shallow Rupture Propagation Of Pleistocene Earthquakes Along The Hurricane Fault, Ut, Revealed By Hematite (U-Th)/He Thermochronometry And Textures, Madison P. Taylor, Alexis K. Ault, Margaret L. Odlum, Dennis L. Newell

Geoscience Faculty Research

The material properties and distribution of faults above the seismogenic zone promote or inhibit earthquake rupture propagation. We document the depths and mechanics of fault slip along the seismically active Hurricane fault, UT, with scanning and transmission electron microscopy and hematite (U-Th)/He thermochronometry. Hematite occurs as mm-scale, striated patches on a >10 m2 thin, mirror-like silica fault surface. Hematite textures include bulbous aggregates and cataclasite, overlain by crystalline Fe-oxide nanorods and an amorphous silica layer at the slip interface. Textures reflect mechanical, fluid, and heat-assisted amorphization of hematite and silica-rich host rock that weaken the fault and promote rupture propagation. …

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Transcontinental Retroarc Sediment Routing Controlled By Subduction Geometry And Climate Change (Central And Southern Andes, Argentina), Eduardo Garzanti, Tomas Capaldi, Giovanni Vezzoli, Mara Limonta, Numa Sosa Sep 2021

Transcontinental Retroarc Sediment Routing Controlled By Subduction Geometry And Climate Change (Central And Southern Andes, Argentina), Eduardo Garzanti, Tomas Capaldi, Giovanni Vezzoli, Mara Limonta, Numa Sosa

Geoscience Faculty Research

Central Argentina from the Pampean flat-slab segment to northern Patagonia (27°–41°S) represents a classic example of a broken retroarc basin with strong tectonic and climatic control on fluvial sediment transport. Combined with previous research focused on coastal sediments, this actualistic provenance study uses framework petrography and heavy-mineral data to trace multistep dispersal of volcaniclastic detritus first eastwards across central Argentina for up to ca. 1,500 km and next northwards for another 760 km along the Atlantic coast. Although detritus generated in the Andes is largely derived from mesosilicic volcanic rocks of the cordillera, its compositional signatures reflect different tectono-stratigraphic levels …

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Localization Of Native Mms13 To The Magnetosome Chain Of Magnetospirillum Magneticum Amb-1 Using Immunogold Electron Microscopy, Immunofluorescence Microscopy And Biochemical Analysis, Zachery Oestreicher, Carmen Valverde-Tercedor, Eric Mumper, Lumarie Pérez-Guzmán, Nadia N. Casillas-Ituarte, Concepcion Jimenez-Lopez, Dennis A. Bazylinski, Steven K. Lower, Brian H. Lower Jul 2021

Localization Of Native Mms13 To The Magnetosome Chain Of Magnetospirillum Magneticum Amb-1 Using Immunogold Electron Microscopy, Immunofluorescence Microscopy And Biochemical Analysis, Zachery Oestreicher, Carmen Valverde-Tercedor, Eric Mumper, Lumarie Pérez-Guzmán, Nadia N. Casillas-Ituarte, Concepcion Jimenez-Lopez, Dennis A. Bazylinski, Steven K. Lower, Brian H. Lower

Life Sciences Faculty Research

Magnetotactic bacteria (MTB) biomineralize intracellular magnetite (Fe3O4 ) crystals surrounded by a magnetosome membrane (MM). The MM contains membrane-specific proteins that control Fe3O4 mineralization in MTB. Previous studies have demonstrated that Mms13 is a critical protein within the MM. Mms13 can be isolated from the MM fraction of Magnetospirillum magneticum AMB-1 and a Mms13 homolog, MamC, has been shown to control the size and shape of magnetite nanocrystals synthesized in-vitro. The objective of this study was to use several independent methods to definitively determine the localization of native Mms13 in M. magneticum AMB-1. Using Mms13-immunogold labeling and transmission electron microscopy …

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Barriers To And Uncertainties In Understanding And Quantifying Global Critical Mineral And Element Supply, Brian A. Mcnulty, Simon M. Jowitt Jul 2021

Barriers To And Uncertainties In Understanding And Quantifying Global Critical Mineral And Element Supply, Brian A. Mcnulty, Simon M. Jowitt

Geoscience Faculty Research

The critical minerals and elements are natural substances that are essential to modern life but have insecure supply. This lack of a secure supply clashes with the increasing importance of these elements, especially given their use in technologies needed to reduce global CO2 emissions and mitigate against anthropogenic climate change. In this contribution we review the by-product nature of the critical minerals and elements and the inherant uncertainties in reported critical mineral and element annual production as well as the relationships between these commodities and main-product metals and associated concentrates. We explore the geological and geographical barriers to critical mineral …

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Calcium Isotope Cosmochemistry, Maria C. Valdes, Katherine R. Bermingham, Shichun Huang, Justin I. Simon Jun 2021

Calcium Isotope Cosmochemistry, Maria C. Valdes, Katherine R. Bermingham, Shichun Huang, Justin I. Simon

Geoscience Faculty Research

The past decade has seen significant advancements in analytical capabilities and with it a marked increase in the use of Ca isotopes to advance our understanding of the Solar System's and Earth's evolution. Here, mass-dependent and non-mass-dependent Ca isotopic variations in bulk meteorites and chondrite components are discussed. This contribution also examines how Ca isotopes record nebular processes, including evaporation/condensation and mixing of chemically and isotopically distinct reservoirs in the protoplanetary disk. The applicability of non-mass-dependent Ca isotopic variations to tracing the nature and timing of stellar mass contributions to the parental molecular cloud is discussed. This includes the constraints …

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The Pitfalls, Perils, And Promise Of Hydrophilanthropy, David K. Kreamer Jun 2021

The Pitfalls, Perils, And Promise Of Hydrophilanthropy, David K. Kreamer

Geoscience Faculty Research

No abstract provided.

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Coupled Deep-Mantle Carbon-Water Cycle: Evidence From Lower-Mantle Diamonds, Wenzhong Wang, Oliver Tschauner, Shichun Huang, Zhongqing Wu, Yufei Meng, Hans Bechtel, Ho Kwang Mao May 2021

Coupled Deep-Mantle Carbon-Water Cycle: Evidence From Lower-Mantle Diamonds, Wenzhong Wang, Oliver Tschauner, Shichun Huang, Zhongqing Wu, Yufei Meng, Hans Bechtel, Ho Kwang Mao

Geoscience Faculty Research

Diamonds form in a variety of environments between subducted crust, lithospheric and deep mantle. Recently, deep source diamonds with inclusions of the high-pressure H O-phase ice-VII were discovered. By correlating the pressures of ice-VII inclusions with those of other high-pressure inclusions, we assess quantitatively the pressures and temperatures of their entrapment. We show that the ice-VII-bearing diamonds formed at depths down to 800 ± 60 km but at temperatures 200–500 K below average mantle temperature that match the pressure-temperature conditions of decomposing dense hydrous mantle silicates. Our work presents strong evidence for coupled recycling of water and carbon in the …

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Cumulative Infiltration And Infiltration Rate Prediction Using Optimized Deep Learning Algorithms: A Study In Western Iran, Mahdi Panahi, Khabat Khosravi, Sajjad Ahmad, Somayeh Panahi, Salim Heddam, Assefa M. Melesse, Ebrahim Omidvar, Chang Wook Lee May 2021

Cumulative Infiltration And Infiltration Rate Prediction Using Optimized Deep Learning Algorithms: A Study In Western Iran, Mahdi Panahi, Khabat Khosravi, Sajjad Ahmad, Somayeh Panahi, Salim Heddam, Assefa M. Melesse, Ebrahim Omidvar, Chang Wook Lee

Civil and Environmental Engineering and Construction Faculty Research

Study region: Sixteen different sites from two provinces (Lorestan and Illam) in the western part of Iran were considered for the field data measurement of cumulative infiltration, infiltration rate, and other effective variables that affect infiltration process. Study focus: Soil infiltration is recognized as a fundamental process of the hydrologic cycle affecting surface runoff, soil erosion, and groundwater recharge. Hence, accurate prediction of the infiltration process is one of the most important tasks in hydrological science. As direct measurement is difficult and costly, and empirical models are inaccurate, the current study proposed a standalone, and optimized deep learning algorithm of …

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Climatic And Topographic Control Of The Stable Isotope Values Of Rivers On The South Island Of New Zealand, Matthew S. Lachniet, Christopher M. Moy, Christina Riesselman, Haroon Stephen, Andrew M. Lorrey May 2021

Climatic And Topographic Control Of The Stable Isotope Values Of Rivers On The South Island Of New Zealand, Matthew S. Lachniet, Christopher M. Moy, Christina Riesselman, Haroon Stephen, Andrew M. Lorrey

Geoscience Faculty Research

We show that climate and topography control the spatial distribution of stable isotope values on the South Island of New Zealand, based on a spatially dense (n = 193) river isotopic survey. Our data show a δ O minimum in isotope values east of the Southern Alps that demonstrates topographically driven continentality associated with the Southern Alps, which intersect the prevailing, moisture-laden westerlies. Our data define a South Island surface water line of δ H = 8.17 (±0.26) × δ O + 10.57 (±2.04), which is identical within 95% confidence intervals to the global and New Zealand meteoric water lines …

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Molybdenite Re–Os, Titanite And Garnet U–Pb Dating Of The Magushan Skarn Cu–Mo Deposit, Xuancheng District, Middle–Lower Yangtze River Metallogenic Belt, Yue Li, Feng Yuan, Simon M. Jowitt, Fangyue Wang, Xiangling Li, Yufeng Deng, Yunyue Wang, Taofa Zhou May 2021

Molybdenite Re–Os, Titanite And Garnet U–Pb Dating Of The Magushan Skarn Cu–Mo Deposit, Xuancheng District, Middle–Lower Yangtze River Metallogenic Belt, Yue Li, Feng Yuan, Simon M. Jowitt, Fangyue Wang, Xiangling Li, Yufeng Deng, Yunyue Wang, Taofa Zhou

Geoscience Faculty Research

© 2020 Elsevier B.V. The Magushan skarn Cu–Mo deposit is a representative example of the skarn mineralization occurring within the Xuancheng ore district of the Middle–Lower Yangtze River Metallogenic Belt of eastern China. The precise age of an ore deposit is important for understanding the timing of mineralization relative to other geological events in a region and to fully place the formation of a mineral deposit within the geological context of other processes that occur within the study area. Here, we present new molybdenite Re–Os and titanite and andradite garnet U–Pb ages for the Magushan deposit and use these data …

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Petrogenesis Of Hawaiian Lavas: Investigations Using Radiogenic And Non-Traditional Stable Isotopes, Christopher Defelice May 2021

Petrogenesis Of Hawaiian Lavas: Investigations Using Radiogenic And Non-Traditional Stable Isotopes, Christopher Defelice

UNLV Theses, Dissertations, Professional Papers, and Capstones

Earth’s mantle is the most voluminous part of the planet and is inaccessible to direct investigations. It is only possible to study it through indirect methods, such as the chemical makeup of erupted lavas. The Hawaiian Islands are thought to be the product of the mantle plume hypothesis, sometimes called a hot spot. Material from the Earth’s mantle is brought to the surface and erupted as magnesium rich lavas and form basalts. Hawaii is the longest lived active hot spot on Earth and makes it an ideal candidate for understanding the evolution of the Earth’s mantle and how lavas cool …

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Extreme Event Reconstructions For The Upper Fraser River Basin, British Columbia, Canada, Inga K. Homfeld May 2021

Extreme Event Reconstructions For The Upper Fraser River Basin, British Columbia, Canada, Inga K. Homfeld

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spring freshets and summer droughts have recently worsened in the Fraser River Basin, British Columbia, Canada, with significant impacts to the keystone Pacific salmon populations, the food and economic sovereignty of over eighty First Nations, and the western Canadian economy. These extreme events present a potential risk since, unlike many large and less hydroclimatically-complex and/or empounded watersheds, the Fraser River Basin is susceptible to a combination of unregulated spring freshet and summer drought events even within the same year. A major limitation for understanding past and future extreme event risk in the Fraser River Basin is that observational streamflow datasets …

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Chronicling Magma Transit Beneath Hawaiian Volcanoes: Every Isotope A Word, Every Crystal A Story, Jonathan Pinko May 2021

Chronicling Magma Transit Beneath Hawaiian Volcanoes: Every Isotope A Word, Every Crystal A Story, Jonathan Pinko

UNLV Theses, Dissertations, Professional Papers, and Capstones

At many oceanic volcanoes, such as Hawaii, mantle-derived magmas migrate to crustal level magma chambers, where they accumulate before eruption. Understanding the magma chamber residence times, or the time gaps between the arrivals of new magmas and eruptions, is important in volcanic hazard mitigation. Here I apply iron and magnesium isotope effects in olivines to constrain these times at Hawaiian volcanoes. Combined with published data, I present bulk ?56Fe (-1.706 to 0.489) and ?26Mg (-0.400 to 0.356) in 108 Hawaiian olivines erupted from the pre-shield, shield, and post-shield stages. The Hawaiian olivine ?56Fe and ?26Mg represent the largest Fe-Mg isotope …

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Prograde Metamorphism And Upper-Crustal Cooling In The Northern Panamint Range, California: New Insights Into The Jurassic And Mid-Cretaceous Evolution Of The Southern Sevier Fold-Thrust Belt, Elijah A. Turner May 2021

Prograde Metamorphism And Upper-Crustal Cooling In The Northern Panamint Range, California: New Insights Into The Jurassic And Mid-Cretaceous Evolution Of The Southern Sevier Fold-Thrust Belt, Elijah A. Turner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Jurassic-Cretaceous southern Sevier fold-thrust belt, which experiences changes in orientation and structural style as it approaches intersection with the Mesozoic continental arc, has been pervasively overprinted by Neogene-Quaternary faulting, rendering its evolution enigmatic. Raman spectroscopy of carbonaceous material (RSCM) thermometry data from 14 samples and zircon (U-Th)/He (ZHe) thermochronology data from 23 samples collected in the northern Panamint Range illuminate the history of metamorphism and upper-crustal cooling associated with this belt of shortening structures. Best estimate peak temperatures derived from RSCM thermometry increase from 166 ± 19°C at 2.5 km structural depth (measured from the top of the exposed …

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Equation Of State For Natural Almandine, Spessartine, Pyrope Garnet: Implications For Quartz-In-Garnet Elastic Geobarometry, Suzanne R. Mulligan, Elissaios Stavrou, Stella Chariton, Oliver Tschauner, Ashkan Salamat, Michael Wells, Alexander G. Smith, Thomas D. Hoisch, Vitali Prakapenka Apr 2021

Equation Of State For Natural Almandine, Spessartine, Pyrope Garnet: Implications For Quartz-In-Garnet Elastic Geobarometry, Suzanne R. Mulligan, Elissaios Stavrou, Stella Chariton, Oliver Tschauner, Ashkan Salamat, Michael Wells, Alexander G. Smith, Thomas D. Hoisch, Vitali Prakapenka

Geoscience Faculty Research

The equation of state (EoS) of a natural almandine74spessartine13pyrope10grossular3 garnet of a typical composition found in metamorphic rocks in Earth’s crust was obtained using single crystal synchrotron X-ray diffraction under isothermal room temperature compression. A third-order Birch-Murnaghan EoS was fitted to P-V data and the results are compared with published EoS for iron, manganese, magnesium, and calcium garnet compositional end-members. This comparison reveals that ideal solid solution mixing can reproduce the EoS for this intermediate composition of garnet. Additionally, this new EoS was used to calculate geobarometry on a garnet sample from the same rock, which was collected from the …

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Manganese Oxides In Martian Meteorites Northwest Africa (Nwa) 7034 And 7533, Yang Liu, Woodward W. Fischer, Chi Ma, John R. Beckett, Oliver Tschauner, Yunbin Guan, Usha F. Lingappa, Samuel M. Webb, Vitali B. Prakapenka, Nina L. Lanza, Carl B. Agee Apr 2021

Manganese Oxides In Martian Meteorites Northwest Africa (Nwa) 7034 And 7533, Yang Liu, Woodward W. Fischer, Chi Ma, John R. Beckett, Oliver Tschauner, Yunbin Guan, Usha F. Lingappa, Samuel M. Webb, Vitali B. Prakapenka, Nina L. Lanza, Carl B. Agee

Geoscience Faculty Research

We report the discovery of indigenous Mn-oxides in Martian regolith breccias Northwest Africa (NWA) 7034 and 7533. These Mn-oxides occur in Mn-rich regions as nanocrystals mixed with silicates, FeOOH, and possible phosphates. The Mn-rich regions contain up to 34 wt% Mn and typically display large chemical gradients on the scale of 10–20 μm. The Martian origin of Mn-oxides was established by the presence of Mn-rich glass (4.8–5.6 wt% Mn) in the fusion crust that crosscuts a Mn-oxides-bearing monzonite clast and by the absence of Mn-oxides on the environmentally exposed surfaces (exterior and fractures) of the meteorites. Manganese K-edge X-ray absorption …

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