Active eruption seen on East Pacific Rise

Abstract

Investigators involved in the ADVENTURE program, an Alvin dive program on the East Pacific Rise crest at 9°–10°N, have reported evidence suggesting very recent and possibly ongoing eruptive activity along this portion of the mid‐ocean ridge. Preliminary age dating of basalt samples from the new flows (Figure 1) suggest that the eruption did, in fact, occur during the March–April 1991 dive program.The East Pacific Rise (EPR) between 9° and 10°N has been the site of much marine geological and geophysical research over the past decade. Research in this region has included a host of interdisciplinary field programs such as numerous high‐resolution multibeam and side‐looking sonar surveys, multichannel seismic and high‐resolution tomographic surveys, a near‐bottom refraction survey, ARGO optical/acoustical nearbottom mapping, and closely spaced rock sampling along the crest and upper flanks of the EPR in this area.