Scientists find dome of ‘violent’ submarine volcano off the coast of Baja, California

Scientists have discovered one of the world’s weirdest volcanoes on the seafloor near the tip of Baja, Mexico. The petite dome about 165 feet tall (50 meters) and 4,000 feet long by 1,640 feet wide (1,200 m by 500 m) lies along the Alarcón Rise, a seafloor-spreading center. Tectonic forces are tearing the Earth’s crust apart at the spreading center, creating a long rift where magma oozes toward the surface, cools and forms new ocean crust. Circling the planet like baseball seams, seafloor-spreading centers (also called mid-ocean ridges) produce copious amounts of basalt, a low-silica content lava rock that makes up the ocean crust. But samples from the newly discovered volcano are strangely rhyolite lava, and have the highest silica content (up to 77 percent) of any rocks collected from a mid-ocean ridge, said Brian Dreyer, a geochemist at the University of California, Santa Cruz.

The results were presented last week at the annu

al meeting of the American Geophysical Union. Researchers with the Monterey Bay Aquarium Research Institute (MBARI) discovered the volcano this spring, during a three-month expedition to the Gulf of California, the warm stretch of water that separates Baja from mainland Mexico. A remote-control vehicle explored the volcano, which is 7,800 feet (2,375 m) below the surface, and brought samples back to the ship. “When we picked up the rocks and got them back on the ship, we immediately noticed that they were very low density, and they were very light, glassy and gray. They were not the usual dark, black, shiny basalts,” Dreyer told OurAmazingPlanet. “So we immediately knew that something was unusual.” The volcano is primarily rhyolite and a silicic lava called dacite, said MBARI geologist Jennifer Paduan.“To find this along a mid-ocean ridge is a total surprise,” she told OurAmazingPlanet.

Boulders and blocks the size of cars and small houses littered the steep slopes of the dome, the robot’s video camera showed. Of more concern is the evidence for explosive volcanism, which is typical of rhyolite volcanoes, Paduan said. “It’s only 100 kilometers [60 miles] from land. When the sun is setting, you can see Cabo,” she said. Both the Baja Peninsula and mainland Mexico near Alarcón Rise have cities and luxury resorts. The Gulf of California is also home to endangered sea life. Rhyolite lava carries more gas and volatiles (things that are likely to cause explosions) than basalt, and when magma meets water, it vaporizes instantly, driving an even more explosive eruption. “There’s definitely explosive deposits there, and that is of extreme concern, given that the ridge is so close to land and the tsunami potential of a big explosion there,” Paduan said. “We don’t know how explosive, and that is something we are definitely trying to figure out.”

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Japan’s Mt Sakurajima Volcano Exploded (This is the 7th Volcano to Erupt Since yesterday)

Japan’s Mt Sakurajima Volcano Exploded in dramatic fashion on Thursday, captured on four cameras set up the Japanese Ministry of Land, Infrastructure and Transport. (This is the 7th Volcano to Erupt Since yesterday)

Guatemala volcano Santiaguito erupts

The Santiaguito volcano, in western Guatemala, erupted today with “very strong,” with the release of smoke and ash at high altitudes, so the agency has recommended Meteorology restrict air traffic in the area. So far there is no need for an evacuation of the villages closest to the volcano, which is located about 227 kilometers from Guatemala City. The director of the National Institute of Seismology, Volcanology, Meteorology and Hydrology (Insivumeh), Eddy Sanchez, reported that the activity of the volcano at 2,550 meters, and located in the department of Quetzaltenango, started at about 5.30 local time (11.30 GMT ). Sanchez added that the sand and volcanic ash is dispersed within at least a 4 kilometers radius of the volcano. “There is a crater collapse, pyroclastic flows, and notice has already been given to Civil Aviation to restrict air operations in that region,” said the director of the local radio Insivumeh. He also reported they warned the National Coordinator for Disaster Reduction (Conrad) to take the necessary precautions. Sanchez said the eruption of Santiaguito will last for several hours and urged people to stock up surrounding drinking water because the sand and volcanic ash can contaminate streams that may be harmful to health. The sand and ash has fallen in populations of the departments of Quetzaltenango and Retalhuleu, where they can be affected coffee plantations, according to Sanchez. The volunteer fire departments of these two departments have declared orange alert or prevention, while experts Conrad Insivumeh and keep a constant eye on the evolution of the eruption.

Kamchatka’s Plosky Tolbachik volcano erupts for first time in 36 years

The 3,085-meter Plosky Tolbachik Volcano in Russia’s Far Eastern Kamchatka Peninsula is Erupting for the first time in 36 years, according to reports of KVERT, the he volcano monitoring body for Kamchatka. The volcano is located on the peninsula’s eastern coast, 343 km from the region’s capital of Petropavlovsk-Kamchatsky. A bulletin released Tuesday by the Kamchatka Volcanic Eruption Response Team (KVERT), as cited by The Voice of Russia, described a significant explosive eruption with the potential for ash explosions up to 10 km. The eruption at Plosky Tolbachik was given code orange (number three on the four-tiered USGS Volcano Alert Level), meaning it “poses limited hazards.” Scientists say the volcano is obscured by clouds at now, but lava intrusions towards the volcano’s summit caldera are also probable. An ash fall was reported in the nearby village of Krasny Yar. The eruption will be closely monitored for its impact on air travel over the eastern Siberian peninsula. The Plosky Tolbachik volcano erupted only 10 times since records began in 1740.

EMO observes intense volcanic activity on Pagan

An intense volcanic activity was monitored by the CNMI Emergency Management Office and captured through satellite images from Nov. 24, 2012, to the present. The volcano has been emitting steam and gas since Friday, Nov. 24, 2012. The vog shows that it’s heading south from Pagan volcano. A gas plume from Pagan has been observed in MODIS satellite images. Minor steam and gas plumes from Pagan have been seen as well. It is possible that the plume could be followed by an ash emission; the presence of a gas plume does not necessarily indicate that eruptive activity will occur soon. Pagan is not monitored with ground-based geophysical instrumentation and the only source of information is satellite observation and occasional reports from observers who visit the island. Also an intense earthquake was recorded at the EMO and National Earthquake Information Center yesterday at 5:34pm Saipan time. The preliminary magnitude is 5.3 on the Richter scale. It was centered some 45 km (27 miles) south of Pagan, Northern Mariana Islands and 276 km (171 miles) north of Saipan, Northern Mariana Islands. Base on all available data no tsunami is expected and there is no tsunami threat for the Marianas.

Indonesia’s Mount Lokon volcano erupts

Mount Lokon volcano in North Sulawesi erupted on Wednesday, spewing ash up to 3.5 kilometers to the sky, without report of fatality and evacuation, officials said. Head of National Volcanology Surono said that the eruption took place at 10:05 local time (0205 GMT). He said that the agency had asked people living near the crater to be alert. “We issued warning to the people living 2.5 kilometers from the crater,” Surono told Xinhua by phone. Spokesman of National Disaster Management and Mitigation Agency (BNPB) Sutopo Purwo Nugroho confirmed that there was no evacuation after the eruption. “There is still no need for evacuation,” he told Xinhua by phone. Indonesia, an archipelago country, is home to 129 active volcanoes.