NW Rota-1 Volcano Erupts

NW Rota-1 Submarine Volcano Located Near Guam Erupts

NW Rota-1, a submarine volcano located about 100km north of Guam in the Marianas Volcanic Arc is erupting.

Scientists and engineers have reportedly been collecting data on NW Rota-1 since early April,  Guam Pacific Daily News reported.

“They were aboard the R/V Thompson research vessel, which was docked briefly at Apra Harbor on Friday. They found the volcano erupting when they visited the area several days ago. The Marianas arc expedition is one of several scientific investigations put together by the National Ocean and Atmospheric Administration’s Pacific Marine Environmental Laboratory.” GuamPDN said.

NW Rota-1

Region:  Mariana Islands
Volcano Type:  Submarine volcano
Last Known Eruption: 2008
Summit Elevation:  -517 m    (-1,696 feet)
Latitude:  14.601°N  (14°36’4″N)
Longitude: 144.775°E  (144°46’31″E)
Source: GVP

A map showing part of the Northern Mariana Islands and vicinity (an area roughly midway between the main island of New Guinea on the S, and Tokyo, Japan on the N). The islands shown include Guam, Rota, Saipan, and others. The map emphasizes the location of the active submarine volcano NW Rota 1 and the currently quiet submarine caldera West Rota. After Embley and others, 2004; courtesy of the American Geophysical Union. Caption: GVP

A submarine volcano detected during a 2003 NOAA bathymetric survey of the Mariana Island arc was found to be hydrothermally active and named NW Rota-1. The basaltic to basaltic-andesite seamount rises to within 517 m of the sea surface SW of Esmeralda Bank and lies 64 km NW of Rota Island and about 100 km north of Guam. When Northwest Rota-1 was revisited in 2004, a minor submarine eruption from a vent named Brimstone Pit on the upper south flank about 40 m below the summit intermittently ejected a plume several hundred meters high containing ash, rock particles, and molten sulfur droplets that adhered to the surface of the remotely operated submersible vehicle. The active vent was funnel-shaped, about 20 m wide and 12 m deep. NW Rota-1 is large submarine volcano with prominent structural lineaments about a kilometer apart cutting across the summit of the edifice and down the NE and SW flanks. Courtesy of Bill Chadwick, 2006 (Oregon State University/NOAA). Caption: GVP.

Bathymetry of NW Rota 1 showing the location of Brimstone Pit, [March 2004]. Credit: Bob Embley, NOAA.

Glowing red lava jetting out of the vent at Northwest Rota-1 Brimstone Pit at depth of 560 m. Photo taken from the submersible Jason II, 29 April 2006. Image courtesy of Submarine Ring of Fire 2006 Exploration, NOAA Vents Program. Caption: GVP

Eruption at Brimstone Pit in Northwest Rota-1 at a depth of 560 m. Photo taken by the submersible Jason II, 29 April 2006. Image courtesy of Submarine Ring of Fire 2006 Exploration, NOAA Vents Program. Caption: GVP

“Our observations here are some of the first direct observations of an erupting submarine volcano ever,” wrote NOAA oceanographer Sharon Walker in an e-mail to the Pacific Daily News. “We have made several visits to this volcano since 2003, with the first confirmation of an active eruption during our 2004 visit.”

“The scientists analyzed samples of seawater around the volcano, measured the rock and deposits, and studied the microbe, shrimp, and limpet populations living atop NW Rota-1.” GPDN said.

“Studying the chemistry of these volcanoes can help provide a better understanding of how excessive amounts of carbon dioxide affect marine environments,” Walker added.

The NW Rota-1 summit is about 517 meters below the sea level.

“There have been no reports that I am aware of that this eruption has had any effect on Rota, Guam or any of the surrounding islands,” wrote Walker.

Walker and her colleagues observed “billowing clouds of yellow and white smoke” made of sulfur, carbon dioxide bubbles streaming out of the vent, and “ash and pebble-sized rocks raining out of the plume.”

More … http://www.guampdn.com/article/20090420/NEWS01/904200310/1002

See also:  Visit on 24 February 2008 found eruption plume and acoustic signals