The violent rise and collapse of an underwater volcano in the Pacific Ocean is captured in startling clarity for the first time.

Researchers studying the Monowai volcano, near Tonga, recorded huge changes in height in just two weeks.

The images, gathered by sonar from a research ship, shed new light on the turbulent fate of submarine mountains.

Published in the journal Nature Geoscience, the findings were made during a seabed survey last year.

Underwater wonder

Lead author Tony Watts of Oxford University told the BBC that the revelation was "a wake-up call that the sea-floor may be more dynamic than we previously thought."

"I've spent my career studying the seabed and have generally thought it pretty stable so it's stunning to see so much change in such a short space of time."

As many as 32,000 underwater mountains have been identified around the world and the majority are believed to be volcanic in origin. Several thousand of these may be active but a combination of ocean depth and remoteness means that very few have been studied.

Concern is growing about a possible eruption of Mt. Baekdu, the highest mountain on the Korean Peninsula, says this article by Park Chang-seok.

A South Korean geological expert has warned that the volcano - which last erupted in 1702 - could erupt sometime around 2014 and 2015.

If the volcano, located on the border between North Korea and China erupts, damage could be 10 to 100 times greater than that caused by the April 2010 eruptions in Iceland.

One of the largest known eruptions in the past 10,000 years occurred at Baitoushan Volcano (Mt. Baekdu) around 1000 A.D., depositing erupted material as far away as northern Japan - a distance of approximately 1,200 kilometers.

Sometimes billed as the largest eruption in the history of mankind, the eruption of the 2,744 meter-high mountain was about 50 times stronger than that of Mt. Vesuvius in 79 A.D. which buried and destroyed the Italian city Pompeii.

Santiago Xalitzintla, Mexico - Mexico's Popocatepetl volcano spewed out huge clouds of ash and fiery rock overnight, closing a local airport on Saturday and frightening nearby villagers, already on edge after weeks of increased activity.

Popocatepetl, 50 miles southeast of Mexico City, shook with tremors that belched out four large plumes of ash on Friday night and Saturday morning, the National Center for Disaster Prevention said in a statement on Saturday.

The biggest expulsion shot an ash cloud 2.5 miles into the air and launched glowing rocks more than half a mile from the crater, the statement said.

Raul Arambula, a scientist collaborating with the government's disaster center, said the volcano threw out the most ash and fragments of red-hot rock since authorities raised the alert level last month.

"It was spectacular," Arambula said. "Of course, it makes you worry about everyone living nearby."

In Santiago Xalitzintla, a village about 6 miles from the volcano, the loud rumblings sent residents running to the town square during the night.

This is going to be a short blog post. As I am going to be short of table and a cheer for few more days.

It seems that Katla volcano is warming up for a eruption. As I did mention in last blog post. But there is more to this. As the glacier flood that started on the 28. April 2012 continues according to a email that I got from an geologist working at Iceland Meteorological Office. But that suggests two things. That there is currently an ongoing melting of glacier taking place in Katla volcano, or there is a slow drainage taking place from some area in Mýrdalsjökull glacier. But given increased conductivity following this it is clear that this water has been in contact with magma. But that can be seen with the increased conductivity in the water.

There have not been many earthquakes following this events. But from the earthquakes that have happened. It seems that most likely source for current events is close to or the same area that erupted in July 2011. But at the moment this is just speculation based on limited data. It has not been confirmed so far.

An active fault as long as 30 km may lie directly beneath Mount Fuji, a team of researchers has said in a recent survey report. The possible fault was detected through a simulated earthquake conducted during a crustal survey over a distance of around 34 km from Fujiyoshida in Yamanashi Prefecture to Susono in Shizuoka Prefecture, said Hiroshi Sato, professor at the Earthquake Research Institute at the University of Tokyo.

A NASA satellite has captured a dramatic image of steam and gas plumes from a volcano in the Mariana Islands in the Pacific Ocean, U.S. scientists said.

The image shows the activity on Pagan Island, the largest and one of the most active of the Marianas volcanoes, a NASA release reported Thursday.

Fires and smoke on the island was imaged on Tuesday by the Moderate Resolution Imaging Spectroradiometer instrument aboard NASA's Terra satellite.

Yes, one! There's only one thing about which they think in a same way - a concern about possible eruption of Mt. Baekdu. The two Koreas remain at odds in everything. But they are one in voicing how to counter the possible volcanic explosion of the highest mountain in the Korean Peninsula

Inter-Korean anxiety is mounting, with growing apocalyptic predictions on the dormant volcano. A South Korean geological expert has warned that the volcano could erupt sometime around 2014 and 2015.

Former North Korean leader Kim Jong-il reportedly said people in some regions of Yanggang and North Hamgyeong Provinces were feeling anxiety over a volcanic eruption of Mt. Baekdu. Kim called for quick countermeasures by the North Korean authorities.

If a volcano, located on the border between North Korea and China erupts, damage could be 10 to 100 times greater than that caused by the April 2010 eruptions in Iceland. Experts predict that the ashes would not only hit the neighboring area but damage agriculture and cause serious disruptions in industrial activities and air flights. The Korean Peninsula, China, Japan and Russia would be severely damaged.

A volcanic eruption begins when pressure on a magma chamber forces magma up through the conduit and out the volcano's vents. When the magma chamber is completely filled, the type of eruption partly depends on the amount of gas and silica in the magma. The amount of silica determines how sticky (level of viscosity) the magma is and water provides the explosive potential of steam.

The 2010 Iceland eruption caused enormous disruption to air travel across Western and Northern Europe, although relatively small in size for volcanic eruptions. About 20 countries closed their airspace and it affected hundreds of thousands of travelers. A very high proportion of flights within, to, and from Europe were cancelled, creating the highest level of air travel disruption since the World War II.

Mexico City just 40 miles away from volcano throwing poison gases a mile up into the air over Puebla state

Mexico remains on high alert as the Popocatepetl volcano continuous to spew gas and volcanic ash into the air.

Mexico's National Centre for Disaster Prevention raised the threat level in April to its third highest warning in a seven-step scale. This indicates the possibility of magma expulsion and eruptions of increasing intensity.

A plume of volcanic smoke is seen rising from the appropriately-named Mount Asphyxia volcano, located on Zavodovski Island in the southern Atlantic. The image was acquired on April 27 by NASA's Aqua satellite.

Zavodovski is part of the South Sandwich Islands, a group of 11 British-owned islands located 217 miles southeast of South Georgia, off the tip of South America. Only 3.1 miles wide, the icy island is dominated by the 1,800-foot-high stratovolcano.

Aptly named, the sulphuric fumes from Asphyxia coupled with the stench of penguin droppings -- the island is a breeding ground for millions of chinstrap penguins -- can be suffocating for human visitors.

Nicaraguan Experts reported Sunday more seismic activity at Masaya volcano, about 20 kilometers south of Managua, with an increase in expulsions of sulfur gases, which keeps the disaster warning system in high alert.

According to the report, a crack in the main crater causes higher emissions and a sound similar to a jet engine.

Specialists of the National System for Prevention, Mitigation and Attention to Disasters (SINAPRED) and the Nicaraguan Institute of Territorial Studies (INETER), told the press that they detected this unusual behavior several days ago, but for now there is no reason for alarm.

The INETER geophysics director, Angelica Munoz, told the site El 19 Digital they monitor Masaya's situation closely because of rising emissions and temperature above the normal range.

Technical teams assess the seismic tremor, but there is no emergency declared and the gates of Masaya Volcano National Park remain open to the public, said the director of INETER, Jorge Castro, and the executive secretary of SINAPRED, Guillermo Gonzalez.