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Correlations between molybdenum and iron sulfide minerals were studied to better understand geochemical controls on Mo in deep-sea hydrothermal systems. Molybdenum is found in high concentrations at hydrothermal vents, upwards of 220 nM, and is an important nutrient for nitrogen fixation and microbial metabolism. Biologic growth ceases to occur at 120ºC, so determining phase equilibria involving Mo could provide crucial information on its biological availability. Modern seawater contains abundant molybdenum (~100 nM), although the opposite is likely true in the Archean Ocean when life first began to emerge. Thus, hydrothermal vents could have been a key source of molybdenum for early life. Accordingly, studies of the distribution of Mo and other trace elements in hydrothermal deposits associated with sulfide minerals at the Main Endeavour Hydrothermal Field (Juan de Fuca Ridge, Northeast Pacific Ocean) were studied. Mineralogic and geochemical analyses of the vent deposits were conducted in association with pyrite synthesis experiments to test the effectiveness of pyrite as a sink for Mo at vent conditions. Sharp differences in the abundance of Mo in pyrite were observed as a function of pyrite crystal habits. In general, poorly crystalline, framboidal pyrite was observed to contain nearly an order of magnitude more Mo than far better crystalized euhedral pyrite, underscoring the importance of crystal-chemical controls on the effectiveness of Mo uptake by Fe sulfide minerals. Considering that pyrite in all its textural forms dominates hydrothermal vent mineralization, these results may put constraints on the possible bioavailability of Mo in modern and ancient deep-sea hydrothermal systems.

In the 2000s, dating applications were created on and for mobile devices, including Grindr in 2008 (Grindr, 2015). Previous research on Grindr has primarily focused on users who are cisgender gay men. Now that Grindr proclaims itself a “queer” networking space, research on other LBTQ+ populations who use the application has increased. Still, nonbinary people’s identities and experiences remain understudied. I expand Goffman’s conceptualization of self-presentation to the virtual landscape of Grindr. Specifically, I consider the implication of impression management and stigma on the self-presentation of nonbinary people. I perform a content analysis on the individual profiles of nonbinary users, including visual (pictures) and textual (autobiographical) data. This thesis illuminates the lived experiences of nonbinary users navigating a dating application rooted in homonormativity, monosexuality, and the gender binary.