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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 ...
Crustal accretion and evolution at slow and ultra-slow spreading mid-ocean ridges
(Massachusetts Institute of Technology, 2001)
Half of the ocean crust is formed at spreading centers with total opening rates less than 40 km/Myr. The objective of this Thesis is to investigate temporal variations in active ridge processes and crustal aging at ...
Observations and modelling of deep equatorial currents in the central Pacific
(Massachusetts Institute of Technology, 1988)
Analysis of vertical profiles of absolute horizontal velocity collected in January 1981, February 1982 and April 1982 in the central equatorial Pacific as part of the Pacific Equatorial Ocean Dynamics (PEQUOD) program, ...
Kinetic processes of mantle minerals
(Massachusetts Institute of Technology, 2000)
This dissertation discusses the experimental results designed to constrain the processes of MORB generation. The main focus of this study is to investigate the location and the related processes of the transformation ...
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, ...
Oceanic lithosphere magnetization : marine magnetic investigations of crustal accretion and tectonic processes in mid-ocean ridge environments
(Massachusetts Institute of Technology, 2007)
The origin of symmetric alternating magnetic polarity stripes on the seafloor is investigated in two marine environments; along the ridge axis of the fast spreading East Pacific Rise (EPR) (90 25'-90 55'N) and at Kane ...
Dismantling the deep earth : geochemical constraints from hotspot lavas for the origin and lengthscales of mantle heterogeneity
(Massachusetts Institute of Technology, 2008)
Chapter 1 presents the first published measurements of Sr-isotope variability in olivine-hosted melt inclusions. Melt inclusions in just two Samoan basalt hand samples exhibit most of the total Sr-isotope variability ...
Organic phosphorus in marine sediments : chemical structure, diagenetic alteration, and mechanisms of preservation
(Massachusetts Institute of Technology, 2000)
Phosphorus, an essential nutrient, is removed from the oceans only through burial with marine sediments. Organic phosphorus (Prog) constitutes an important fraction (ca. 25%) of total-P in marine sediments. However, given ...
Subduction in an eddy-resolving state estimate of the northeast Atlantic Ocean
(Massachusetts Institute of Technology, 2004)
Relatively little is known about the role of eddies in controlling subduction in the eastern half of the subtropical gyre. Here, a new tool to study the eastern North Atlantic Ocean is created by combining a regional, ...
The evolution of lithospheric deformation and crustal structure from continental margins to oceanic spreading centers
(Massachusetts Institute of Technology, 2002)
This thesis investigates the evolution of lithospheric deformation and crustal structure from continental margins to mid-ocean ridges. The first part (Ch. 2) examines the style of segmentation along the U.S. East Coast ...