This is a project to conduct a combined seismic and electromagnetic study of the axial volcanic region of a section of the Reykjanes Ridge using the resources of Cambridge and Durham Universitites (UK), Flinders University (Australia), and Scrips Institution of Oceanography (US). The Study will use (1) wide angle seismic profiles along and across an axial volcanic ridge to determine the crustal structure, (2) a detailed electromagnetic sounding experiment centered on the ridge to determine crustal electrical conductivity structure, and (3) an array of long.antenna electric field instruments and magnetometers to determine the deeper conductivity structure in the mantle beneath the ridge axis by both controlled and natural source electromagnetic sounding.