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A magmatic trigger for the Paleocene-Eocene thermal maximum?
(Massachusetts Institute of Technology, 2015)
Fifty-six million years ago Earth experienced rapid global warming (~6°C) that was caused by the release of large amounts of carbon into the ocean-atmosphere system. This Paleocene-Eocene Thermal Maximum (PETM) is often ...
Molecular determination of marine iron ligands by mass spectrometry
(Massachusetts Institute of Technology, 2016)
Marine microbes produce a wide variety of metal binding organic ligands that regulate the solubility and availability of biologically important metals such as iron, copper, cobalt, and zinc. In marine environments where ...
Biogeochemical and phylogenetic signals of Proterozoic and Phanerozoic microbial metabolisms
(Massachusetts Institute of Technology, 2018)
Life is ubiquitous in the environment and an important mediator of Earth's carbon cycle, but quantifying the contribution of microbial biomass and its metabolic fluxes is difficult, especially in spatially and temporally-remote ...
Seismic constraints on the processes and consequences of secondary igneous evolution of Pacific oceanic lithosphere
(Massachusetts Institute of Technology, 2016)
This thesis examines the structure of Pacific oceanic lithosphere that has been modified by post-formation magmatism in order to better understand the processes of secondary magmatic evolution of the lithosphere, which can ...
Linking microbial metabolism and organic matter cycling through metabolite distributions in the ocean
(Massachusetts Institute of Technology, 2017)
Key players in the marine carbon cycle are the ocean-dwelling microbes that fix, remineralize, and transform organic matter. Many of the small organic molecules in the marine carbon pool have not been well characterized ...
Geochemical controls on the distribution and composition of biogenic and sedimentary carbon
(Massachusetts Institute of Technology, 2017)
Organic carbon (OC) preserved in marine sediments acts as a reduced carbon sink that balances the global carbon cycle. Understanding the biogeochemical mechanisms underpinning the balance between OC preservation and ...
Water and volatile element accretion to the inner planets
(Massachusetts Institute of Technology, 2018)
This thesis investigates the timing and source(s) of water and volatile elements to the inner solar system by studying the basaltic meteorites angrites and eucrites. In chapters 2 and 3, I present the results from angrite ...
Reconstructing deglacial ocean ventilation using radiocarbon : data and inverse modeling
(Massachusetts Institute of Technology, 2017)
Significant changes occurred during the last deglaciation (roughly 10-20 thousand years (ka) before present) throughout the climate system. The ocean is a large reservoir of carbon and heat, however, its role during the ...
The biogeochemistry of marine particulate trace metals
(Massachusetts Institute of Technology, 2014)
Marine particles include all living and non-living solid components of seawater, representing an extremely dynamic and chemically diverse mixture of phases. The distributions of these phases are poorly constrained and ...
Greenlandic ice archives of North Atlantic Common Era climate
(Massachusetts Institute of Technology, 2019)
The Common Era (A.D. 1- present) represents a crucial period for climatic studies, documenting the timespan over which human activities have become an increasingly domineering force in shaping Earth's landscape, climate, ...