Mid-Ocean ridge eruptions and the breathing of Axial Volcano

Maya Tolstoy
Lamont-Doherty Earth Observatory

Wednesday, June 21, 2000
3:00 p.m.—Pacific Forum

An understanding of the eruption characteristics of mid-ocean ridges is beginning to emerge through long-term hydroacoustic monitoring. Detailed understanding of the seismicity associated with a seafloor eruption is best achieved through 3-component ocean-bottom seismometer (OBS) studies. However, the expense and limited range of OBS monitoring means that you have to be very lucky to catch volcanism in action on the seafloor. Most of our knowledge on mid-ocean ridge volcanism, therefore, comes from hydroacoustic monitoring.

Evidence for recent volcanism on the ultra-slow spreading Gakkel Ridge, the fast spreading East Pacific Rise, and the intermediate spreading Juan de Fuca Ridge & Galapagos Rise will be presented and the seismic character of this volcanism discussed. Data from an OBS-tiltmeter deployment on Axial Volcano in 1994 will also be presented. These data indicate that in this region, the seafloor seismicity appears to correlate with the tides.