Phuket moved, or maybe it didn’t

PHUKET: There is no proof that Phuket has shifted 15 centimeters to the southwest following the December 26 earthquake, according to Dr Adichart Surinkum of the Geotechnic Division of the Department of Mineral Resources (DMR).

“Evidence is still being collected and displacement modeling is continuing to determine if movement took place,” he told the Gazette today. “Surveying all the areas involved and determining any movement will take around six months.

“Movement – if found – will not be limited to Phuket, or Thailand but to all countries in the area of the earthquake,” he added.

“Coastlines and watercourses could change after such an event,” he warned.

Dr Adichart scotched suggestions that bubbles seen rising to the water’s surface in the Ratchagrud District of Ranong Province are from deep underground.

“They are methane bubbles from decaying plant matter just under the surface of the sand. The earthquake has ‘shaken’ up the area and the gas is being released,” he said.

The DMR has said that 49 provinces – including Phang Nga and Krabi – are at risk from sinkholes.

The announcement from the DMR warns that a loud noise from beneath the ground or the sudden release of water often heralds a new sinkhole.

The DMR advises that anyone in the vicinity of a suspected sinkhole as it forms should retreat some 100 meters or more and stop all excavation or drilling work in the area until the scene is declared safe.

Sinkholes are caused when the rock – typically limestone or carbonate rock – below the surface of the land is dissolved by groundwater circulating through it, although this process usually occurs over a long period of time.

As the rocks are dissolved, caverns form underground. The surface remains intact until it can no longer support its own weight and the “roof” collapses. Sinkholes may vary in size from as little as 1 meter to as large as a house.

The DMR is continuing to look into the phenomenon.