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The influence of ridge geometry at the ultraslow-spreading Southwest Indian Ridge (9⁰-25⁰E) : basalt composition sensitivity to variations in source and process
(Massachusetts Institute of Technology, 2006)
Between 90-25° E on the ultraslow-spreading Southwest Indian Ridge lie two sharply contrasting supersegments. One 630 km long supersegment erupts N-MORB that is progressively enriched in incompatible element concentrations ...
Cenozoic deep-water agglutinated foraminifera in the North Atlantic
(Massachusetts Institute of Technology, 1988)
Magmatism and dynamics of continental breakup in the presence of a mantle plume
(Massachusetts Institute of Technology, 2000)
This thesis studies the dynamics of mantle melting during continental breakups by geophysical, geochemical, and numerical analyses. The first part focuses on the mantle melting and crustal accretion processes during the ...
Insights into vitamin B₁₂ production, acquisition, and use by marine microbes
(Massachusetts Institute of Technology, 2012)
The distribution and magnitude of marine primary production helps determine the ocean's role in global carbon cycling. Constraining factors that impact this productivity and elucidating selective pressures that drive the ...
Physical influences on phytoplankton ecology : models and observations
(Massachusetts Institute of Technology, 2013)
The physical environment in the oceans dictates not only how phytoplankton cells are dispersed and their populations intermingled, but also mediates the supply of nutrients to the surface mixed layer. In this thesis I ...
Gulf stream temperature, salinity and transport during the last millennium
(Massachusetts Institute of Technology, 2006)
Benthic and planktonic foraminiferal [delta]18O ([delta 18Oc) from a suite of well-dated, high-resolution cores spanning the depth and width of the Straits of Florida reveal significant changes in Gulf Stream cross-current ...
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 ...
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, ...