Researchers at the Oregon State University had a surprise when they went to the Axial seamount volcano located about 230 miles off the Oregon coast. Last year they had left instruments to record volcanic activity. When they returned, they found the instruments buried in lava.
The Axial volcano is located on the Juan de Fuca plate near Oregon’s coast. In a previous post I said this is the area Where the Next Big American Earthquake and Tsunami Might Occur.
According to the news release from Oregon State University:
What makes the event so intriguing is that the scientists had forecast the eruption starting five years ago – the first successful forecast of an undersea volcano.
When Axial erupted in 1998, the floor of the caldera suddenly subsided or deflated by 3.2 meters (10.5 feet) as magma was removed from underground to erupt at the surface. The scientists estimated that the volcano would be ready to erupt again when re-inflation pushed the caldera floor back up to its 1998 level.
The discovery of the new eruption came on July 28, when Chadwick, Nooner and University of Washington colleagues Dave Butterfield and Marvin Lilley led an expedition to Axial aboard the R/V Atlantis, operated by the Woods Hole Oceanographic Institution. Using Jason, a remotely operated robotic vehicle (ROV), they discovered a new lava flow on the seafloor that was not present a year ago.
This latest Axial eruption caused the caldera floor to subside by more than two meters (six feet). The scientists will be measuring the rate of magma inflation over the next few years to see if they can successfully forecast the next event.
According to NOAA:
Axial Volcano rises 700 meters above the mean level of the ridge crest and is the most magmatically robust and seismically active site on the Juan de Fuca Ridge between the Blanco Fracture Zone and the Cobb offset. It represents the product of intense volcanic activity from the Cobb-Eikelberg hotspot juxtaposed on the extensional field of the spreading center. Axial Volcano was first studied in the late 1970s and then mapped in greater detail by NOAA/VENTS with SeaBeam in the early 1980s. Following the initial discovery of venting in the northern portion of the caldera in 1983, a concentrated mapping and sampling effort was made in the mid-late 1980s.The summit of Axial Volcano is marked by an unusual rectangular shaped caldera (3 x 8 km) that lies between the two rift zones. The caldera is defined on three sides by a boundary fault of up to 150 m relief. Hydrothermal vents colonized with biological communities are located near the caldera fault or along the rift zones.