NASA Satellite Images Show Pakistan's New Island Formed During Mud Volcano
Posted on September 27, 2013
These NASA images reveal Pakistan's new island. The island was formed by a suspected mud volcano following a 7.7 magnitude earthquake in northwestern Pakistan. The image below was acquired on April 17, 2013 and the image above (showing the new island) was taken on September 26, 2013. The 7.7 magnitude quake struck the Baluchistan province of northwestern Pakistan. The new island formed offshore in the Paddi Zirr (West Bay) near Gwadar, Pakistan.
The aerial photograph below is from the National Institute of Oceanography. The new island is 75 to 90 meters (250 to 300 feet) across and stands 15 to 20 meters (60 to 70 feet) above the water line. It is made of mud, fine sand and solid rock.
Bill Barnhart, a geologist at the U.S. Geological Survey who studies earthquakes in Pakistan and Iran, says in a report from NASA's Earth Observatory, "The island is really just a big pile of mud from the seafloor that got pushed up. This area of the world seems to see so many of these features because the geology is correct for their formation. You need a shallow, buried layer of pressurized gas - methane, carbon dioxide, or something else - and fluids. When that layer becomes disturbed by seismic waves (like an earthquake), the gases and fluids become buoyant and rush to the surface, bringing the rock and mud with them."
Barnhart also says these types of islands usually only last for a few months to a year. They are eroded by waves, storms and tide action. The underground pocket of gas which helped them form will also "cool, compress, or escape over time, allowing the crust to collapse and settle back down."