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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 ...
The marine geochemistry of iron and iron isotopes
(Massachusetts Institute of Technology, 2004)
This thesis addressed questions about the Fe cycle by measuring detailed profiles and transects of Fe species in the ocean and also by exploring the use of a new tracer of Fe, Fe isotopic fractionation. In the subtropical ...
Marine particle dynamics : sinking velocities, size distributions, fluxes, and microbial degradation rates
(Massachusetts Institute of Technology, 2011)
The sinking flux of particulate matter into the ocean interior is an oceanographic phenomenon that fuels much of the metabolic demand of the subsurface ocean and affects the distribution of carbon and other elements ...
The entrainment and homogenization of tracers within the cyclonic gulf stream recirculation gyre
(Massachusetts Institute of Technology, 1987)
The various distributions of tracer associated with the Northern Recirculation Gyre of the Gulf Stream (NRG) are studied to try to obtain information about the flow. An advective-diffusive numerical model is implemented ...
Antarctic glacial chronology : new constraints from surface exposure dating
(Massachusetts Institute of Technology, 2000)
The dynamics of oceanic transform faults : constraints from geophysical, geochemical, and geodynamical modeling
(Massachusetts Institute of Technology, 2008)
Segmentation and crustal accretion at oceanic transform fault systems are investigated through a combination of geophysical data analysis and geodynamical and geochemical modeling. Chapter 1 examines the effect of fault ...
Geomicrobiology of the ocean crust : the phylogenetic diversity, abundance, and distribution of microbial communities inhabiting basalt and implications for rock alteration processes
(Massachusetts Institute of Technology, 2007)
Basaltic ocean crust has the potential to host one of the largest endolithic communities on Earth. This portion of the biosphere, however, remains largely unexplored. In this study, we utilize molecular biological, ...
Helium and lead isotope geochemistry of oceanic volcanic rocks from the East Pacific and South Atlantic
(Massachusetts Institute of Technology, 1987)
The isotopic evolution of helium and lead in the Earth is coupled by virtue of their common radioactive parents uranium and thorium. The isotopic signatures in oceanic volcanic rocks provide constraints on the temporal ...