Category
Indonesian Mud Volcano is Collapsing
Posted on Thursday, May 29, 2008 @ 5:36 am by Dave Schumaker
In 2006, a drilling accident near the city of Sidoarjo, Indonesia caused a large and rapidly growing mud volcano to form. The volcano, named Lusi, eventually went on to become the fastest growing mud volcano in the world, engulfing upwards of 7 square kilometers and forcing 30,000 people from their homes.
New research from Durham University suggests that if the volcano continues erupting at current levels, the area will significantly subside, resulting in the creation of a caldera.
Source: Reuters
Their research used GPS and satellite data recorded between June 2006 and September 2007 that showed the area affected by Lusi had subsided by between 0.5 metres and 14.5 metres per year.
The scientists found that if Lusi continued to erupt for three to 10 years at the constant rates measured during 2007 then the central part of the volcano could subside by between 44 metres and 146 metres – 26 metres longer than a football pitch.
They propose the subsidence is due to the weight of mud and collapse of rock strata due to the excavation of mud from beneath the surface.
Their study has also found that while some parts of Sidoarjo are subsiding others are rising suggesting that the Watukosek fault system has been reactivated due to the eruption.
We previously wrote about this eruption last year.
More Information:
About.com - Watch Lusi Collapse
Highly Allochthonous - Lusi in Time
Guardian - Mud Volcano on Brink of Collapse
[Via Eurekalert]
Video of Mount St. Helens Lava Dome Growth
Posted on Friday, May 23, 2008 @ 12:35 am by Dave Schumaker
Courtesy of the USGS, I received some fascinating b-roll footage relating to Mount St. Helens. By far, the most interesting segment in the 29 minutes of video occurs at the end, a time lapse sequence lasting 4 years, showing the growth of the lava dome inside the crater of Mount St. Helens.
I uploaded that segment of the video into Vimeo for the world to see. Check it out!
Geology Picture of the Day - Mount St. Helens
Posted on Sunday, May 18, 2008 @ 7:50 am by Dave Schumaker
28 years ago today, Washington state’s Mount St. Helens catastrophically erupted, becoming the largest volcanic eruption in the lower 48 states.
Image credit: USGS
Geology Picture of the Day - Mount Cleveland Eruption
Posted on Friday, May 16, 2008 @ 10:24 am by Dave Schumaker
This is a picture taken from the International Space Station of Mount Cleveland, located in Alaska, erupting in June of 2006.
Image credit: Astronaut Jeffrey Williams and NASA.
More information on Mount Cleveland and its eruptions can be found at the Alaska Volcano Observatory website.
Geology Picture of the Day - Pahoehoe
Posted on Wednesday, May 14, 2008 @ 8:19 am by Dave Schumaker
A type of lava formed from very fluid basaltic flows is called pahoehoe. In today’s geology picture of the day, we see a beautiful example of ropey pahoehoe from Hawaii Volcanoes National Park.
For more information on the types of lava, visit Instant Hawaii.
One of the more interesting types of pahoehoe lava is called ropey pahoehoe and looks like a series of twisted ropes spaced evenly along the ground. The twisted ropes may be fairly straight, or may loop and wind in and out much like a fingerprint. Many visitors express interest in what could create such an unusual shape, but once you see ropey pohoehoe lava being created it is instantly clear how the shapes occur. As the pahoehoe flows, it usually encounters some minor barrier that slows up the front of the flow. As the front of the flow is slowing down, the faster flow behind it pushes the front and forces it to create a small ridge, which it pushes up and over the barrier. That ridge begins to cool and creates the next barrier, which in turn creates the next. The result is a series of ridges interspaced with valleys - which looks like 4 inch thick ropes of lava laying side by side or looping side by side. To walk over ropey pahoehoe it is best to walk on the top of the ridges, perpendicular to the ridges.