A moderately large vulcanian explosion occurred this morning, producing significant fallout of lapilli and small bombs in several kilometers distance. Cars parked at the Arimura Lava observatory observation point to the south of the volcano were damages and windshields broken, at a distance of about 4 km. There are no reports of injuries to people.

The world's largest volcano lurks beneath the Pacific Ocean, researchers announced today (Sept. 5) in the journal Nature Geoscience.

Called the Tamu Massif, the enormous mound dwarfs the previous record holder, Hawaii's Mauna Loa, and is only 25 percent smaller than Olympus Mons on Mars, the biggest volcano in Earth's solar system, said William Sager, lead study author and a geologist at the University of Houston.

"We think this is a class of volcano that hasn't been recognized before," Sager said. "The slopes are very shallow. If you were standing on this thing, you would have a difficult time telling which way was downhill."

Tamu is 400 miles (650 kilometers) wide but only about 2.5 miles (4 km) tall. It erupted for a few million years during the early Cretaceous period, about 144 million years ago, and has been extinct since then, the researchers report.

On Saturday morning (Aug. 24), residents of Rome were startled to discover that a steaming vent, spitting out a steady stream of water and mud, had erupted from the ground near a runway at Rome's busy Fiumicino airport.

Geologists and engineers are investigating the vent to ensure that it's not a broken pipe or some other accident, according to VolcanoDiscovery. Assuming that it's not manmade, it could be a fumarole, a vent of steaming-hot hydrothermal water that erupts at the Earth's surface.

"There are a lot of hot springs in the area around Rome, so it might not be surprising that new vents could open," Erik Klemetti, assistant professor of geosciences at Denison University in Granville, Ohio, told LiveScience.

"Likely this doesn't lead to anything more than maybe a new hot spring, if it is related to the normal geothermal activity across the area," Klemetti said. "Once volcanologists can sample the gases being emitted, we might have a better idea of what the ultimate source of the vent might be."

It's been erupting constantly for nearly 60 years, spewing out smoke and ash and sending shivers through the more than half a million people who live nearby. Japan's Sakurajima volcano recently blasted 100,000 tonnes of ash more than five kilometres into the sky, reminding surrounding communities of its power and volatility. Vulcanologists warn that the magma chamber beneath the mountain is about 90 per cent full, meaning that a large lava eruption cannot be ruled out.

The ABC's North Asia correspondent Mark Willacy travelled to Sakurajima in south-west Japan to see how people live with this rumbling giant.

In legend, this belching giant was named for a beautiful goddess, the divine being venerated as the symbol of delicate earthly life. But Sakurajima is anything but delicate. It is the mother of all Japanese volcanos. Just across the water from the city of Kagoshima, it is both a tourist drawcard and a troublesome neighbour. And for our visit on this perfect summer's day, the mountain is putting on yet another show.

Sakurajima is one of the world's most active volcanos. Some years it belches into life or erupts over 1,000 times and this bad-tempered beast is just eight kilometres from the 600,000 residents of Kagoshima.

Residents of Eagle, Alaska, are getting worried about possibly toxic gases wafting into town from a mysterious underground fire on a nearby mountain that's been burning for almost a year.

Nobody seems to know exactly what's burning. Experts suspect it's either a volcano forming or natural gas or oil burning in underground shale deposits. Whatever it is, the fire has been burning on a remote mountaintop, about 40 kilometres north of the community since last October at least.

When the wind is right, residents can smell noxious smoke all over town.

Italian experts have been puzzled by the overnight appearance of a geyser crater spraying clouds of gas 15 feet in the air, yards from the end of the runway at one of Europe's busiest airports.

Motorists on Saturday were alarmed to notice hot, stinking gas spurting from a newly formed crater in the middle of a roundabout close to the perimeter fence of Rome's Fiumicino airport -- less than 900 yards from the end of a runway.

Spectators gathered around the smoking crater, which measured about six feet wide and three feet deep, before firefighters and vulcanologists arrived to seal off the roundabout to prevent inhalation of the gas, suspected to be a cocktail of carbon dioxide, hydrogen sulphide and methane. Tests are now underway.

While initial reports suggested the gas came from rotting organic matter trapped underground, one expert said volcanic activity was more likely.

Mount Hobalt, an underwater volcano off the coast of Lembata island, East Nusa Tenggara, briefly erupted on Tuesday but did not cause any damage, officials and residents said. "Based on information received from the head of the Center for Vulcanology and Geological Disaster Mitigation [PVMBG], the mountain erupted Tuesday morning," Sutopo Purwo Nugroho, the head of the National Disaster Mitigation Agency (BNPB), said. Sutopo called on villagers living around the volcano to remain alert, but added that there was no need for residents to be evacuated from the area. "The PVMBG is closely monitoring the volcano," Sutopo said. Petrus Bote, who heads the district's disaster mitigation office, said that district authorities were preparing for the possibility of a larger eruption by bolstering stocks of emergency relief supplies and increasing manpower around the area.

"Many people, including fishermen, saw the peak of [Mount Hobalt] surface for a few minutes," Peter said on Tuesday. He said that a similar phenomenon took place when the volcano last erupted in May 1999. Tini Thadeus, the head of the NTT Disaster Mitigation Agency, said that the volcano briefly belched a column of smoke and ash that reached between 1,000 and 2,000 meters above sea level at around 7:13 a.m. on Tuesday. Meanwhile, Victor Mado Watun, the island's deputy district chief, said that another volcano, Mount Ile Wereng, which straddles the inland subdistricts of Atadei and Wulandoni, also experienced a brief eruption. Victor said that a three-kilometer radius danger zone around the two mountains has been declared. "The district's disaster mitigation office has sent two teams to the Atadei and Wulandoni. They are monitoring the activity of two volcanoes there and are registering the number of villagers living near them," Victor said. Hobalt is one of the five active submarine volcanoes in Indonesia, a country that sits on three geological fault lines dotted with volcanoes. - Jakarta Times

Activity has remained elevated. A series of ash emissions caused by moderately strong vulcanian-type explosions occurred over the past days. This morning, an ash plume rose to 8,000 ft (2.4 km) altitude and drifted east. Meanwhile, Shiveluch: The volcano continues to extrude a new lobe of viscous lava (visible as the dark patch in the webcam image) at the lava dome, as well as produce occasional (usually small) ash explosions - Volcano Discovery

A major eruption occurred yesterday evening. Starting at 17:45 (local time), the top part of the Caliente lava dome collapsed and produced a series of relatively large pyroclastic flows and explosions. Ash plumes rose more than 2 km to elevations of 4 km altitude. The cause of the eruption was likely the accumulation of pressurized magma and gas under the dome composed of viscous (solid) lava. The pyroclastic flows affected mainly the south, southeast and NNE sides. Bombs from explosive activity were ejected to distances of 500 m. - Volcano Discovery

Jakarta - Indonesian authorities have been warning local villagers in East Nusa Tenggara Province about increasing volcanic activities in the area in recent days.

"The people around the areas should continue to practice caution" despite there not having been fresh volcanic activity on Wednesday, said Sutopo Purwo Nugroho, the spokesman of the National Disaster Mitigation Agency.

The agency reported on Tuesday two volcanoes in the East Nusa Tenggara Province have shown "increasing activities." The volcanoes are subsea Mount Hobalt and and Mount Ili Werung.

It noted Mount Hobalt erupted Tuesday morning, spewing cloud as high as 6,560 feet above the sea level for around two minutes.