Japan's Sakurajima Volcano Has Largest Eruption In Decades

Sakurijima volcano, a large stratovolcano located within the Aira Caldera, has had its nearly 500th eruption of 2013, and this one has shattered some records. A massive gas and ash plume rose above the volcano today, reaching 16,000 ft or more (5,000+ meters) into the sky. Ash rained down on nearby towns and people are using rags and masks to breathe if they venture outside. Video footage showed a large explosion of dark ash, followed by a large plume of grey ash rising far above the volcano.

According to Japan's Meteorological Society, this is the highest ash plume since records began being kept in 1955. Sakurijima is one of Japan's most active volcanoes. Although fatalities are quite rare, it has killed in the past with pyroclastic flow. Currently there is a several km wide exclusion radius from the summit area, so injuries are rare as well.

600,000 residents are currently experiencing ashfall and should remain indoors if possible. Inhaling volcanic ash can be deadly or cause serious damage to lung functions, as well as it being an extreme irritant to your eyes. Volcanic ash is made up of very tiny particles of volcanic glass, and literally cut through your soft tissue, making your life miserable.

Sakuriajima has been in a heightened state of eruption for the last decade or so, erupting frequently and powerfully. 

Indonesia's Mt Rokatenda (Paluweh) Erupts, Killing 6

Indonesia's Mount Rokatenda erupted today, killing 6 and evacuating over 3000 from the island of Pulaweh. The volcano had been showing signs of unrest since October 2012. Three adults and two children are confirmed dead, while the sixth person remains unidentified. The bodies have not been recovered as the eruption is ongoing, and efforts are focused on evacuations.  The bodies of two adults have since been recovered, however the bodies of the children remain on the island.

It was later confirmed that the victims were killed by pyroclastic flow, one of the most deadly and swift effects of explosive eruptions. Those who have been evacuated will be relocated to nearby Flores Island.

Google Earth image of Rokatenda (Paluweh) island

Image of the Eruption from NBCnews.com

From the images, the eruption appears to be explosive and pyroclastic in nature. Pyroclastic flows are able to accelerate when travelling over the ocean's or other water bodies' surface. The island is about 11 miles from the nearest shore. It would be inadvisable to stay near this shore until activity calms down. If any updates are posted, I will update this post.

Idonesia is part of the so-called "Ring of Fire' a 'loop' of volcanoes spanning the boundaries of the Pacific tectonic plate. Eruptions on the Ring of Fire are from some of the world's most active volcanoes

100,000 Reader Milestone!

I am very happy to say that since the launch of this blog, I have hit over 100,000+ page views! Thank you all very much for reading my blog, and I hope it has been as fun for you to read as I have writing it! I launched this blog in part because I felt there was a lack of good American-English reading volcanology blogs, and I wanted to create a site where people could read about current eruptions, earthquakes, and access some very cool online geology resources. I hope I have achieved that goal!

Thank you all for reading!

-Matt

Yellowstone Geyser Erupts For First Time In 8 Years

Yellowstone National Park, and its enormous super volcano is home to more than half of the world's geothermal geysers. There are probably not a lot of people in the world who aren't familiar with the name "Old Faithful", one of the most famous geysers in the world, known for its punctual eruption timing, and spectacular steam and water spouts. Yellowstone on Wednesday got quite the surprise when one of it's less-reliable geysers had a sudden - and massive - burst of steam that rose nearly 400 feet into the air for about 40 minutes.

It has been 8 years since "Steamboat geyser" has erupted. It is one of the most random geysers in the park, and dwarfs the eruptions of "old Faithful" (to be clear, the term eruption refers only to hydrothermal activity, not magmatic in nature). Video on NBCnews.com shows the hastily recorded cell phone footage from surprised guests (unfortunately it's not terribly great, and you cannot see the beginning of the blast).

Yellowstone is home to 300 or more active or potentially active geysers, with even more hot springs, and other hydrothermal features. The last magmatic eruption of Yellowstone occurred somewhere around 1350 BCE, creating the Indian Pond crater. Some scientists believe Yellowstone is 'overdue' for a major eruption, but of course this is speculation, and very specific conditions would need to occur for a modern day super-eruption to take place. If an eruption does occur in the near future, it would likely be a small effusive, or minor explosive event, much like the Indian pond event.

The magma chamber that is the source for the geothermal heat in the are is vast, but cooling. It is made up of what scientists refer to as a 'crystal mush', or partially cooled lava. It would take a very large injection of fresh magma and gasses to initiate an eruption in Yellowstone, and no injections have been detected in recent time.

So for now, Yellowstone rises and falls, breathes in and out like a sleeping giant. 

Mauna Loa - Is the Next Eruption Near?

Mauna Loa in Hawaii is the world largest volcano by volume. Rising from the sea floor to its summit, it is one of the largest mountains in the world as well, from foot to summit, being about 56,000 ft... many times taller than even Mt. Everest! It also happens to be Hawaii's most active volcano, although you wouldn't know it given its recent slumber. It actually erupts more often than Kilauea, last having erupted about the same time that Kilauea started its current eruption, in 1984, a year after Kilauea started its current eruption. This eruption cause massive lava flows that paved over towns/villages, and caused a lot of property damage (hence the big islands ridiculous insurance prices).

Mauna Loa has erupted 33 times since 1843 (and many many times before) making it one of the worlds most active and massive volcanoes.

Mauna Loa has been mostly quiet since its last eruption. The volcano currently has some active fumeroles, hot springs, and still-degassing areas from the last eruption, but that may be about to change, as HVO has detected heightened seismicity and inflation of a shallow magma reservoir. Could Mauna Loa be gearing up for another eruption? It is probable, as Mauna Loa is 'overdue' for an eruption.

HVO's current reporting of Mauna Loa indicates that deformation has been mostly dominated by slow south-easterly motion of its south flank (toward the active Kilauea volcanic complex), but more recently, increased inflation of about 1cm/year at the summit caldera, which does indicate new magma injection, and a possible precursor to an eruption in the near future. It is definitely worth keeping an eye on Mauna Loa.

While it is highly unlikely that an eruption of Mauna Loa would cause any human casualties, the potential for massive amounts of property damage, and damage to ecosystems on the island is high. During the 1984 eruption, vast swaths of land were covered by lava, and in some areas, houses were built on these lava flows, which have a high likelihood of getting hit by a lava flow again. Any areas that did not have a lava flow would be at risk due to lava pooling or gravity drawing in a flow.

The next eruption of Mauna Loa would likely be quite a sight to behold. Most volcanic eruptions in Hawaii do not generate pyroclastic flows, or anything more than fast or slow moving pahoehoe lava flows, fissure eruptions, however there have been cases of crater forming eruptions that do prove a bit dangerous. I for one will be keeping a close eye on Mauna Loa, as the eruption will be spectacular, no matter what the mountain does. And the fact that Hawaii has some of the best webcam coverage of its volcanoes means that many would get to see the eruption take place in real-time! Stay tuned!