Scripps Scientists Image Deep Magma beneath Pacific Seafloor Volcano

Vast mantle melting region below world's largest volcanic system advances theory of plate tectonics. Since the plate tectonics revolution of the 1960s, scientists have known that new seafloor is created throughout the major ocean basins at linear chains of volcanoes known as mid-ocean ridges. But where exactly does the erupted magma come from? During a 2004 expedition aboard R/V Roger Revelle, researchers deployed an electromagnetic instrument off Central America. Researchers at Scripps Institution of Oceanography at UC San Diego now have a better idea after capturing a unique image of a site deep in the earth where magma is generated. Using electromagnetic technology developed and advanced at Scripps, the researchers mapped a large area beneath the seafloor off Central America at the northern East Pacific Rise, a seafloor volcano located on a section of the global mid-ocean ridges that together form the largest and most active chain of volcanoes in the solar system. By comparison, the researchers say the cross-section area of the melting region they mapped would rival the size of San Diego County. Study site for the 2004 expedition at the northern East Pacific Rise, a mid-ocean ridge volcano where new seafloor is created as the Pacific and Cocos tectonic plates diverge.