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The effect of a shallow low viscosity zone on mantle convection and its expression at the surface of the earth
(Massachusetts Institute of Technology, 1987)
Many features of the oceanic plates cannot be explained by conductive cooling with age. A number of these anomalies require additional convective thermal sources at depths below the plate: mid-plate swells, the evolution ...
The CAFE experiment : a joint seismic and MT investigation of the Cascadia subduction system
(Massachusetts Institute of Technology, 2013)
In this thesis we present results from inversion of data using dense arrays of collocated seismic and magnetotelluric stations located in the Cascadia subduction zone region of central Washington. In the migrated seismic ...
Chemical, isotopic, and temporal variations during crustal differentiation : insights from the Dariv Igneous Complex, Western Mongolia
(Massachusetts Institute of Technology, 2016)
Fractional crystallization of mantle-derived basaltic melts is a critical process in producing a compositionally stratified continental crust characterized by a silicic upper crust and a mafic lower crust. This thesis ...
Seismic and gravitational studies of melting in the mantle's thermal boundary layers
(Massachusetts Institute of Technology, 2007)
This thesis presents three studies which apply geophysical tools to the task of better understanding mantle melting phenomena at the upper and lower boundaries of the mantle. The first study uses seafloor bathymetry and ...
The marine biogeochemistry of molybdenum
(Massachusetts Institute of Technology, 2003)
Prevailing wisdom holds that the vertical distribution of molybdenum (Mo) in the open ocean is conservative, despite Mo's important biological role and association with Mn oxides and anoxic sediments. Mo is used in both ...
Trace element proxies and mineral indicators of hydrothermal fluid composition and seafloor massive sulfide deposit formation processes
(Massachusetts Institute of Technology, 2017)
This thesis analyzes compositions of seafloor massive sulfide (SMS) deposits and related hydrothermal vent fluids to identify proxies of reaction zone conditions (host-rock lithology, hydrothermal fluid temperature and ...
Determining timescales of natural carbonation of peridotite in the Samail Ophiolite, Sultanate of Oman
(Massachusetts Institute of Technology, 2012)
Determining timescales of the formation and preservation of carbonate alteration products in mantle peridotite is important in order to better understand the role of this potentially important sink in the global carbon ...
Basalt petrogenesis beneath slow- and ultraslow-spreading Arctic mid-ocean ridges
(Massachusetts Institute of Technology, 2009)
To explore the ability of melting mafic lithologies to produce alkaline ocean-island basalts (OIB), an experimental study was carried out measuring clinopyroxene (Cpx)melt and garnet (Gt)-melt partition coefficients during ...
Quaternary morphology and paleoenvironmental records of carbonate islands
(Massachusetts Institute of Technology, 2014)
Here I use a simple numerical model of reef profile evolution to show that the present-day morphology of carbonate islands has developed largely in response to late Pleistocene sea level oscillations in addition to variable ...
Climate controls on coral growth in the Caribbean
(Massachusetts Institute of Technology, 2013)
Accurate predictions of Caribbean coral reef responses to global climate change are currently limited by a lack of knowledge of the dominant environmental controls on coral growth. Corals exhibit significant responses to ...