Lamont-Doherty Earth Observatory, Columbia University
East Pacific Rise at 9ºN
Top, surface view of sea-floor topography. Main panel, colors show log[resistivity (ohm-m)] in the vertical direction obtained from nonlinear inversion of data from the sea-floor magnetotelluric stations (inverted triangles in surface view). Green to red colours indicate high conductivity (low resistivity) due to partial melts generated in the upwelling mantle. Solidus depths for dry and wet peridotite are shown as horizontal lines.In February 2004 we carried out an extensive EM survey across the Northern East Pacific Rise near 9º30′ N. The goals of this experiment were to image the upper mantle and crustal magmatic system associated with plate spreading volcanism at this fast-spreading mid-ocean ridge. Using the R/V Roger Revelle, we collected 69 sites of broadband marine MT data and towed the new Scripps deep-tow EM transmitter SUESI for over 80 km, resulting in the largest marine MT and controlled-source EM data set ever collected at a mid-ocean ridge.
