Thorough understanding of the mechanisms controlling the temperature structure in the surface mixed layer of the ocean and, in particular, accurate values of sea surface temperature are critical for properly parameterizing air-sea heat exchange and quantifying the amount of heat redistributed below the surface. It is however difficult to obtain...
Tropical coral reef ecosystems are very important from both the ecological and economical
points of view. However, they are also particularly fragile, and have been
declining in recent years in most regions of the world, since they are highly susceptible
to anthropogenic stressors operating at global scales (e.g., global warming...
In this thesis, data collected during the Dynamics of the Madden Julian Oscillation (DYNAMO) field campaign, conducted in the Indian Ocean in Fall of 2011, is used to compute heat fluxes at the air-sea interface by evaluating eddy covariances and bulk aerodynamic formulae. Errors in daily average gridded fluxes computed...
Subduction zone earthquake and tsunami hazards affect tens of millions worldwide and the recurrence of these disasters can be evaluated with paleoseismic techniques, because earthquake cycles (and their supercycles) typically span many millennia. In these three chapters, I discuss a suite of analyses I use to evaluate the sedimentary record...
Prior to eruption at mid-ocean ridges, melts must travel through >6 km of crust from their origin in the mantle. The final composition of the melts is dependent on both the melting conditions and magmatic processes within the crust. While mid-ocean ridge basalt (MORB) glasses are commonly used to infer...
In an attempt to understand the phase equilibria and petrogenesis of MORB anorthitic plagioclase, Cr-spinel commonly hosted within anorthitic plagioclase has been investigated petrographically and compositionally. Based on spinel-anorthite relationships from three samples of plagioclase ultra-phyric basalt (PUB; Southeast Indian Ridge, Axial Seamount and West Valley Segment, Juan de Fuca...
The Kane Oceanic Core Complex (OCC) is a valuable window into crustal architecture and chemical composition of the lithosphere beneath a slow-spreading ocean ridge. A suite of > 30 samples (comprised of whole rocks, mineral separates and basalt glasses) has been analyzed for ³He/⁴He isotope ratios and He concentrations. Gas...
Recent studies have found that equatorial Atlantic sea surface temperature (SST) variability may be influencing tropical Indian Ocean climate (Kucharski 2009, Wang 2009). Due to the economic and social impact of tropical cyclones, it is important to investigate how an Atlantic-Indian Ocean connection may be affecting tropical cyclone behavior in...
The seismicity at the northern section of the Gorda Ridge has been
studied with Ocean Bottom Seismographs. Nearly one hundred earthquakes
were located with RMS travel time residuals less than 0.5 seconds.
Most of these events lie within or near the array and they are probably
associated with the dynamics...
We have determined the seismic crustal structure of the
northern part of the Gorda Ridge using signals generated by
explosive charges and recorded on Ocean Bottom Seismometers. The
shot pattern forms two parallel lines, one on the east flank and the
other along the median valley. Inversion of the travel...