Current Research
The water content of planetesimalsThis work constrains the types of materials (e.g., chondrites) that could have been a primary source of H (or water) to the Earth. I use in situ methods such as SIMS and FTIR to measure the highly volatile element (e.g., H, C, F, Cl, and S) content of nominally anhydrous minerals and glasses in chondrites, primitive achondrites, and achondrites. I combine geochemical and petrologic data to reconstruct the volatile content of parent bodies and meteorite groups. I've found that small, melted planetesimals are extremely H-poor, suggesting that H loss from small, melted bodies is efficient. My work on the ureilites has been published in GCA and my work on the aubrites has been published in EPSL. Works on additional groups are in review.
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Mineral-melt H2O partitioning at ≤ 100 MPaI conducted mineral-melt H2O partitioning experiments at pressures ≤ 100 MPa in cold-seal pressure vessels using basaltic and basaltic andesitic starting compositions. Experimental run products include olivine, plagioclase, and glass allowing me to constrain mineral-melt partition coefficients for olivine and feldspar. These data will help to inform models of magma storage and ascent and the H2O content of meteoritic parent bodies. These manuscripts are in prep, but I am happy to discuss preliminary results.
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Former Research
Flood basalt chemostratigraphyI gathered major and trace element data using LA-ICP-MS of thick sections to assess the origin of the Makonnen basalts. The Makonnen are a volumetrically small pulse of magmatism that were originally thought to precede the Oligocene East African Rift volcanics. My work demonstrated that they were related to the onset of Oligocene magmatism. My work was published as part of Steiner et al. (2022).
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CI-normalized spider-diagram showing the tight correlation between the Makonnen basalts and the Oligocene Gamo and HT1 basalts.
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SEM image of a grain from HWMK600, a tephra sample from Mauna Kea, HI. This grain shows distinct cracking on the surface due to weathering.
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Micro-textural analysis of Mars Regolith analogsI conducted an SEM investigation of micro-textural features of a Mars regolith analog from Mauna Kea, HI. I compared these features with climactic conditions and prior work to assess if micro-textural features can be used to assess climatic conditions.
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