This is a project to determine the time of origin, linkage to mantle upwelling, and mode of development of cross-grain gravity rolls on the southern East Pacific Rise. The principal Investigators will carry out SeaMARC II and gravity surveys of 0 to 6 million year old crust on west flank of the East Pacific Rise between 16 and 19 South. The extensive SeaMARC coverage will also be used to address problems relating to the evolution of large offset overlapping spreading centers. %%% SeaMARC II is a sea floor mapping tool that is used extensively to provide extensive bathymetric and side scan imagery. The data will provide important information on the morphology and tectonic history of the sea floor and will also assist in making better determinations of topographic corrections to the gravity data. The cross grain gravity rolls are anomalous features originally detected in satellite data. These interesting and anomalous features have not been thoroughly studied from a surface ship. The Principal Investigators have provided leadership in the area of marine tectonics and gravity data interpretation for many years. They are uniquely well qualified for this study.
