Search
Now showing items 111-120 of 654
Dynamics of global ocean heat transport variability
(Massachusetts Institute of Technology, 1999)
A state-of-the-art, high-resolution ocean general circulation model is used to estimate the time-dependent global ocean heat transport and investigate its dynamics. The north-south heat transport is the prime manifestation ...
Zinc and cadmium in benthic foraminifera as tracers of ocean paleochemistry
(Massachusetts Institute of Technology, 2000)
Benthic foraminiferal δ13C, Cd/Ca, and Ba/Ca are important tools for reconstructing nutrient distributions, and thus ocean circulation, on glacial-interglacial timescales. However, each tracer has its own "artifacts" that ...
Mechanisms of turbulent mixing in the Continental Shelf bottom boundary layer
(Massachusetts Institute of Technology, 2000)
The bottom boundary layer is an important dynamical region of shallow water flows. In this thesis, the problem of turbulent mixing in the coastal bottom boundary layer is investigated with a unique set of field measurements ...
Centennial-scale elemental and isotopic variability in the tropical and subtropical North Atlantic Ocean
(Massachusetts Institute of Technology, 2002)
The marine geochemistry of the North Atlantic Ocean varies on decadal to centennial time scales, a consequence of natural and anthropogenic forcing. Surface corals provide a useful geochemical archive to quantify past mixed ...
Petrologic and microstructural constraints on focused melt transport in dunites and the rheology of the shallow mantle
(Massachusetts Institute of Technology, 2004)
Observations at mid-ocean ridges indicate that magmas are focused to the ridge axis by a network of porous dunites in near chemical isolation. This thesis investigates several of the outstanding questions regarding the ...
The paleoceanography of the Bering Sea during the last glacial cycle
(Massachusetts Institute of Technology, 2006)
In this thesis, I present high-resolution stable-isotope and planktonic-fauna records from Bering Sea sediment cores, spanning the time period from 50,000 years ago to the present. During Marine Isotope Stage 3 (MIS3) at ...
Generation and maintenance of recirculations by Gulf Stream instabilities
(Massachusetts Institute of Technology, 1999)
This thesis studies the problems of generation and maintenance of recirculations by Gulf Stream instabilities. Observations show that the horizontal structure of the jet and its recirculations suffer significant changes ...
Temporal and petrogenetic constraints on volcanic accretionary processes at 9-10 degrees North East Pacific Rise
(Massachusetts Institute of Technology, 2010)
Volcanic accretion at the fast-spreading East Pacific Rise (EPR) occurs over a ~2-4 km wide neo-volcanic zone on either side of the axial summit trough (AST). Eruption ages are critical for understanding the distribution ...
Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean
(Massachusetts Institute of Technology, 2014)
At the land-ocean interface, terrestrial groundwater interacts with seawater to form a subterranean estuary, which can play host to dynamic biogeochemical cycling of nutrients, trace metals and radionuclides. This chemically ...
Novel analytical strategies for tracing the organic carbon cycle in marine and riverine particles
(Massachusetts Institute of Technology, 2017)
Particulate organic carbon (POC) in the ocean and mobilized by rivers on land transfers -0. 1% of global primary productivity to the deep ocean sediments. This small fraction regulates the long-term carbon cycle by removing ...