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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 ...
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 ...
Interactions between mantle plumes and mid-ocean ridges : constraints from geophysics, geochemistry, and geodynamical modeling
(Massachusetts Institute of Technology, 2001)
This thesis studies interactions between mid-ocean ridges and mantle plumes using geophysics, geochemistry, and geodynamical modeling. Chapter 1 investigates the effects of the Marion and Bouvet hotspots on the ultra-slow ...
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 ...
An investigation into the characteristics and sources of light emission at deep-sea hydrothermal vents
(Massachusetts Institute of Technology, 2000)
A spectral camera (ALISS - Ambient Light Imaging and Spectral System) was used to image ambient light from high-temperature vents at 9°N East Pacific Rise and the Juan de Fuca Ridge during 1997 and 1998 Alvin dive cruises. ...
Fine-grained sedimentation on the Chenier Plain Coast and inner continental shelf, northern Gulf of Mexico
(Massachusetts Institute of Technology, 2003)
This thesis examines the evolution of a mud-dominated coastal sedimentary system on multiple time scales. Fine-grained systems exhibit different properties and behavior from sandy coasts, and have received relatively little ...
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 ...
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 ...