A5018668041- Astro and Planetary Science
- Planetary Science and Exploration
- Geological and Geochemical Analysis
- High-pressure geophysics and materials
- Space Exploration and Technology
- Isotope Analysis in Ecology
- Geochemistry and Geologic Mapping
- Geology and Paleoclimatology Research
- Radioactive element chemistry and processing
- Paleontology and Stratigraphy of Fossils
- Geomagnetism and Paleomagnetism Studies
- Metallurgical Processes and Thermodynamics
- earthquake and tectonic studies
- Hydrocarbon exploration and reservoir analysis
- Geochemistry and Elemental Analysis
- Marine and environmental studies
- Mineralogy and Gemology Studies
- Scottish History and National Identity
- Glass properties and applications
- Nuclear Physics and Applications
- Innovative Human-Technology Interaction
- Discourse Analysis in Language Studies
- Spacecraft and Cryogenic Technologies
- Space Science and Extraterrestrial Life
- Social Media and Politics
University of Massachusetts Dartmouth
2023
Brighton and Sussex Medical School
2021
Lunar and Planetary Institute
2018-2021
East Carolina University
2018-2020
The Ohio State University
1999-2020
Federal Reserve Bank of Richmond
2020
University of Arizona
1982-2019
Johns Hopkins University Applied Physics Laboratory
2019
Planetary Science Institute
1986-2019
Goddard Space Flight Center
2019
Stable isotope ratios of H, C, and O are powerful indicators a wide variety planetary geophysical processes, for Mars they reveal the record loss its atmosphere subsequent interactions with surface such as carbonate formation. We report in situ measurements isotopic D/H (18)O/(16)O water (13)C/(12)C, (18)O/(16)O, (17)O/(16)O, (13)C(18)O/(12)C(16)O carbon dioxide, made martian at Gale Crater from Curiosity rover using Sample Analysis (SAM)'s tunable laser spectrometer (TLS). Comparison...
The launch of ChatGPT in November 2022 precipitated a panic among some educators while prompting qualified enthusiasm from others. Under the umbrella term Generative AI, is an example range technologies for delivery computer-generated text, image, and other digitized media. This paper examines implications education one generative AI technology, chatbots responding large language models, or C-LLM. It reports on application C-LLM to review assessment complex student work. In concluding...
Abstract— Many solar system processes involve a metallic liquid, and the composition of such as liquid's concentrations S, P, C, will influence partitioning elements during processes. We present method for parameterizing solid metal‐liquid metal partition coefficients siderophile (metal‐loving) function liquid composition. Our parameterization is based on an older theory Jones Malvin (1990), which stated that composed non‐metal‐bearing domains, domains are dominant behavior. By revising...
The behavior of water and other volatiles on Mars is key to understanding the evolution climate. early climate played a fundamental role in producing observed surface morphology possibly enabling existence an biosphere. Geochemical isotopic data can be used infer history volatiles. On basis from atmosphere components (as measured meteorites that come Mars), there appear at least two reservoirs volatiles, one has undergone exchange with been isotopically fractionated, second unfractionated...
The ureilite meteorites are carbonaceous olivine‐pyroxene achondrites. They typically contain up to 4 wt.% carbon (carbonaceous matrix) as graphite, diamond, and lonsdaleite. Shock degradation has effectively obliterated primary textures in the matrix of previously described ureilites, a factor that hampered efforts explain origin this material. In contrast, Antarctic ALHA78019 displays perfectly preserved characterized by euhedral graphite blades intergrown with Fe‐Ni metal sulfide...
The partitioning behavior of Cr into olivine in basaltic systems has been parameterized and can now be modeled over a wide range redox conditions liquid compositions. Cr2+/Cr3+ spinel-saturated experimental estimated based on simple model solubility basalt. Fe3+ appears to suppress the presence Cr2+ systems. We predict that, Fe-free systems, all is trivalent at log fO₂ = -3 (i.e.. QFM+3 QFM+4). whereas approximately Ni-NiO(QFM+1) Fe- bearing predominates under <IW-1 both Fe-bearing
Liquid carbonate/ liquid silicate partition coefficients (D) for a suite of incompatible elements (Nb, Mo, Ba, Ce, Pb, Th, U) have been determined experimentally. For one experiment, D's Ra and Pa were also determined. The partitioning behavior is shown to be regular function the ionic field strength (zr) partitioned elements. At constant temperature, increasing pressure from 7 20 kbar caused little change in measured D. pressure, temperature causes all approach unity, as nears critical two...
Theoretical lunar mantle seismic velocity and density profiles are calculated for a series of proposed bulk compositions, present‐day selenotherms, models early differentiation evolution. The compared to the most recent observational model derived from complete Apollo data set evaluate compositional implications. mean density, moment‐of‐inertia, crustal density/thickness constraints need metallic core. in qualitative agreement with two general respects: (1) quasicontinuous decrease occurs...
This study examines the revision histories of 10 Wikipedia articles nominated for site's Featured Article Class (FAC), its highest quality rating, 5 which achieved FAC and did not. The revisions to each article were coded, coding results combined with a descriptive analysis two representative in order determine patterns. All both groups showed higher percentage additions new material compared deletions that rearranged text. Although had roughly equal numbers content surface revisions,...