West Mata - Explosive Deep-Ocean Volcano

[Astronuc]

Iwo Jima and Japan lie along the western edge of the Pacific Ring of Fire (ROF). During the last 18 months, the seismic and volcanic activity seems to have increased, and along with the Sumatran tsunamis and a few big quakes off North and South America, one has to wonder its all related.

TOKYO (AP) - Japanese coast guard officials said Sunday they believe an underwater volcanic eruption has caused a 3,300-foot high column of steam to rise from the Pacific Ocean near Iwo Jima.

The vapor was reported Saturday after Japanese troops stationed on the small island observed the massive, cloudy plume rise from the sea about 30 miles southeast of the island, said Maritime Self-Defense Forces Hiroshi Shirai.

Defense officials who flew over the area in a helicopter said the surface of the water appeared red where the column was reported, which could indicate underwater volcanic activity, Shirai said.

On Sunday, coast guard aircraft crews flew over the site and returned with a video image confirming the earlier reports, said Shigeyuki Sato, a spokesman for the service. The survey crew also found grayish mud rising up from the bottom of the ocean, but it was not immediately known whether any volcanic gases are being released.

The location is known as Fukutokuoka-no-ba, an undersea volcano which last erupted in 1986 for three days, Sato said.

The coast guard aircraft ended the day's survey after less than two hours due to safety concerns, but plan to return to the site as early as Monday for further monitoring. The service issued an international warning for vessels, urging them to stay away from the waters.

Japan's Meteorological Agency said there was no danger of tsunamis, sometimes caused by undersea seismic activity. Iwo Jima is about 700 miles southeast of Tokyo.

See pics at http://news.yahoo.com/s/ap/20050703/ap_on_sc/japan_underwater_eruption;_ylt=AujOWQrFU1YXH1Jai7bu.5.s0NUE;_ylu=X3oDMTA3MzV0MTdmBHNlYwM3NTM-

 

[Astronuc]

Scientists Discover and Image Explosive Deep-Ocean Volcano
http://www.noaanews.noaa.gov/stories2009/20091217_volcano2.html
NOAA-NSF Mission Adds to Understanding of Basic Earth Processes
December 17, 2009

Scientists funded by NOAA and the National Science Foundation recorded the deepest erupting volcano yet discovered, describing high-definition video of the undersea eruption as “spectacular.” Eruption of the West Mata volcano, discovered in May, occurred nearly 4,000 feet below the surface of the Pacific Ocean, in an area bounded by Fiji, Tonga and Samoa.

Imagery includes large molten lava bubbles approximately three feet across bursting into cold seawater, glowing red vents explosively ejecting lava into the sea, and the first-observed advance of lava flows across the deep-ocean seafloor. Sounds of the explosive eruption were recorded by a hydrophone and later matched to the video footage.

“We found a type of lava never before seen erupting from an active volcano, and for the first time observed molten lava flowing across the deep-ocean seafloor,” said the mission’s Chief Scientist Joseph Resing, a chemical oceanographer at the University of Washington who collaborates with NOAA through the Joint Institute for the Study of the Atmosphere and Ocean. “Though NOAA and partners discovered a much shallower eruption in 2004 in the Mariana Arc, the deeper we get, the closer the eruption is to those that formed most of the oceanic crust.”

. . . .

This area has had some rather significant earthquakes lately. I wonder if they are tied to whatever is driving this volcano?

The summit of West Mata Volcano is nearly a mile below the ocean surface (1,165 meters / 3,882 feet), and the base, shown in blue, descends to nearly two miles (3,000 meters / 9,842 feet) deep. The volcano, located in the Lau basin (15° 5' S, 173° 45' W) near the Tonga Trench, has a six-mile-long rift zone running along its spine in a SW/NE orientation.

http://www.noaanews.noaa.gov/stories2009/images/map_satellite_altimetry_labeled.png

Some big earthquakes nearby.

7.2 Mag - http://earthquake.usgs.gov/earthquakes/eqinthenews/2009/us2009nuam/
Date/Time: Monday, November 09, 2009 at 10:44:54 UTC
Location: 17.212°S, 178.413°E
Depth: 585.1 km (363.6 miles)

6.8 Mag - http://earthquake.usgs.gov/earthquakes/eqinthenews/2009/us2009pja1/
Date/Time: Tuesday, November 24, 2009 at 12:47:14 UTC
Location: 20.641°S, 174.068°W
Depth: 10 km (6.2 miles)

8.0 Mag - http://earthquake.usgs.gov/eqcenter/eqinthenews/2009/us2009mdbi/
Date/Time: Tuesday, September 29, 2009 at 17:48:10 UTC
Location: 15.509°S, 172.034°W
Depth: 18 km (11.2 miles)

Mag 8 was the big quake in Somoa.

6.6 Mag - http://earthquake.usgs.gov/eqcenter/eqinthenews/2009/us2009kybj/
Date/Time: Sunday, August 30, 2009 at 14:51:33 UTC
Location: 15.187°S, 172.526°W
Depth: 11 km (6.8 miles)