For the third time in 15 years, the movement of tectonic plates in the Makran area has caused a methane and mud spewing island to form off the coast of Gwadar in Balochistan, according to the National Institute of Oceanography (NIO), Pakistan.
Tuesday’s powerful (7.7 on the Richter scale) earthquake near Awaran jolted the seismically active Makran zone, director-general of the NIO Dr. Ali Rashid Tabrez told The Hindu on the phone from Karachi. The sea from Gwadar to Ormara had a vast stock of frozen methane gas below the sea bed and it was not uncommon to see bubbles in the water caused by methane gas escaping from fissures, he pointed out.
Explaining the development, he said when there was a seismic movement the gas deposits, which expand creating high pressure, pushed up a land mass of this kind.
The land mass — which had people rushing to the coast to view it — is 50 metres long, 20 to 30 metres wide and rises 10 metres above the water about two km off the coast of Gwadar. There is methane being emitted and mud oozing out. Dr. Tabrez said people shouldn’t go too near since there was some movement below the sea bed. No boating or fishing should be allowed either, he said. The NIO which has a station at Gwadar had sent its technical staff to observe, take samples and photograph the phenomenon. The “island” is made up of soft sediment, mostly mud, sand and even rock fragments, he said. This was observed in 1999 and in 2010 near Ormara, off the Hingol river where it enters the sea.
However, in the past it is observed that these “islands” decline slowly due to constant wave action in the sea. In 1999 it was observed that after four months, it had vanished. The sea bed showed up some remnants of the land mass at that time. This phenomenon was observed as far back as 1945 as well, he said.
Source: The Hindu 26 September 2013