Magmatic processes control the chemical compositions of all lavas erupted at
mid-ocean ridges. In this thesis, I present studies of magmatic processes on three
different mid-ocean ridges to determine which processes are in action and to what extent
each has affected the chemistry of mid-ocean ridge basalts at each location....
Hydroacoustic tertiary (T-) waves are seismically generated acoustic waves that propagate
over great distances in the ocean sound channel with little loss in signal strength.
Hydrophone recorded T-waves can provide a lower earthquake detection threshold and an
improved epicenter location accuracy for oceanic earthquakes than land-based seismic
networks. Thus detection...
The basement of the Tonga intraoceanic forearc comprises Eocene arc volcanic crust formed during the earliest phases of subduction. Volcanic rocks recovered from the forearc include boninites and arc tholeiites, apparently erupted into and upon older mid-oceanic ridge tholeiites. Rock assemblages suggest that the forearc basement is a likely analog...