|Rare island created by Pakistan quake is fragile mass of mud, experts say
A small island created in the Arabian Sea by the earthquake that hit southwest Pakistan has fascinated locals but experts say it is unlikely to last. A marine biologist estimated the island is about 18 to 21 metres high. It sits about 200m from the coast.
The 7.7-magnitude quake struck Tuesday in Baluchistan's remote Awaran district, killing more than 200 people and affecting hundreds of thousands.
Off the coastline near the port of Gwadar, some 400 kilometers from the epicenter, locals were astonished to see a new piece of land surface from the waves.
Mohammad Danish, a marine biologist from Pakistan's National Institute of Oceanography, said a team of experts had visited the island and found methane gas rising.
“Our team found bubbles rising from the surface of the island which caught fire when a match was lit and we forbade our team to start any flame. It is methane gas,'' Danish said on GEO television news.
The island is about 18 to 21 meters high. It is up to 300 feet wide and up to 120 feet long, he said. It sits about 200m from shore.
Gary Gibson, a seismologist with Australia's University of Melbourne, said the new island was likely to be a “mud volcano,’’ created by methane gas forcing material upwards during the violent shaking of the earthquake.
“It's happened before in that area but it's certainly an unusual event, very rare,'' Gibson told AFP.
The so-called island is not a fixed structure but a body of mud that will be broken down by wave activity and dispersed over time, the scientist said.
A similar event happened in the same area in 1945 when an 8.1-magnitude earthquake at Makran triggered the formation of mud volcanoes off Gwadar.
Professor Shamim Ahmed Shaikh, chairman of the department of geology at Karachi University, said the island, which has not been named, would disperse within a couple of months.
He said it happens along the Makran coast because of the complex relationship between tectonic plates in the area. Pakistan sits close to the junction of three plates –
the Indian, Arabian and Eurasian.
“About a year back an island of almost similar size had surfaced at the similar distance from the coast in the Makran region. This would disperse in a week to a couple of months,'' Shaikh told AFP.
Gibson said the temporary island was very different from the permanent uplift seen during major “subduction zone'' earthquakes, where plate collisions force the Earth's crust suddenly and sometimes dramatically upwards.