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Geochemistry of deep-sea hydrothermal vent fluids from the Mid-Cayman Rise, Caribbean Sea
(Massachusetts Institute of Technology, 2015)
This thesis examines the controls on organic, inorganic, and volatile species distributions in hydrothermal fluids venting at Von Damm and Piccard, two recently discovered vent fields at the ultra slow spreading Mid-Cayman ...
Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina
(Massachusetts Institute of Technology, 2015)
Tracing the evolution of Earth's redox history is one of the great challenges of geobiology and geochemistry. The accumulation of photosynthetically derived oxygen transformed the redox state of Earth's surface environments, ...
Evaluating mantle and crustal processes using isotope geochemistry
(Massachusetts Institute of Technology, 2000)
Geochemical studies are fundamental for understanding how the dynamic Earth works and evolves. These studies place constraints on the composition, formation, age, distribution, evolution and scales of geochemically distinct ...
Application of Seasat altimetry to tectonic studies of fracture zones in the Southern oceans
(Massachusetts Institute of Technology, 1987)
Gravity derived from Seasat altimetry has provided a means of estimating seafloor topography and its compensation, which in turn can be used to understand the evolution of oceanic lithosphere. In the first study, the ...
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 ...
Relating the biogeochemistries of zinc, cobalt, and phosphorus to phytoplankton activities in the sea
(Massachusetts Institute of Technology, 2006)
This thesis explores the potential of zinc, cobalt, and phosphorus to influence primary production in the subarctic North Pacific, the Bering Sea, and the North Atlantic Ocean. In the North Pacific and Bering Sea, total ...
Boundary layer dynamics and deep ocean mixing in Mid-Atlantic Ridge canyons
(Massachusetts Institute of Technology, 2013)
Physical oceanographers have known for several decades the total amount of abyssal mixing and upwelling required to balance the deep-water formation, but are still working to understand the mechanisms and locations-how and ...
Thermal and mechanical development of the East African Rift System
(Massachusetts Institute of Technology, 1988)
The deep basins, uplifted flanks, and volcanoes of the Western and Kenya rift systems have developed along the western and eastern margins of the 1300 km-wide East African plateau. Structural patterns deduced from field, ...
Chemical characterization of dissolved organic matter (DOM) in seawater : structure, cycling, and the role of biology
(Massachusetts Institute of Technology, 2005)
The goal of this thesis is to investigate three different areas relating to the characterization of dissolved organic matter (DOM): further determination of the chemical compounds present in high molecular weight DOM ...
Abrupt climate change in the Atlantic Ocean during the last 20,000 years : insights from multi-element analysis of benthic and planktic foraminifera and coupled OA-GCM
(Massachusetts Institute of Technology, 2005)
Minor and trace element records of planktic and benthic foraminifera from Atlantic sediment cores, as well as output from a coupled OAGCM, were used to investigate the magnitude and distribution of the oceanic response to ...