FY 1995

SeaBeam depth changes associated with recent lava flows, CoAxial segment, Juan de Fuca Ridge: Evidence for multiple eruptions between 1981–1993

Chadwick, Jr., W.W., R.W. Embley, and C.G. Fox

Geophys. Res. Lett., 22(2), doi: 10.1029/94GL01895, 167–170 (1995)

After a swarm of earthquakes was detected on the CoAxial segment of the Juan de Fuca Ridge in June-July 1993, the area was resurveyed with SeaBeam multibeam sonar to search for depth changes associated with a submarine volcanic eruption. Quantitative comparison of the 1993 SeaBeam survey with surveys in 1981/82 and 1991 shows one area of seafloor depth change (up to 29 m) between 1991-93 exactly where a pristine lava flow was discovered. In addition, two other depth anomalies (up to 37 m and 20 m) are identified between 1981-91, evidence that other recent eruptions have occurred along this spreading ridge segment.