An island uncovered just six years ago by a chain of natural disasters has once again been swallowed up by the sea.
In 2013 following a 7.7 magnitude earthquake and subsequent mud volcano, scientists noticed a new, oval-shaped island sitting off the coast of western Pakistan.
It measured just 90 meters (295 feet) wide, and experts predicted it wouldn’t be around for long.
Satellite images captured over the last six years show the progression of the short-lived island, from the moment it emerged up until it disappeared.
The island, dubbed Zalzala Koh (meaning ‘Earthquake Mountain’ in Urdu), measured 20 meters high, 90 meters wide, and 40 meters long when it sprang up in a bay near the city of Gwadar in 2013.
Scientists say it was a product of a mud volcano triggered by an earthquake in September of that year.
Mud volcanoes are a common phenomenon in the area due to plate tectonics, where the Arabian plate is sinking beneath the Eurasian plate.
‘The rapid accumulation of soft, clay-rich sediments along the edge of the Eurasian plate combined with the high tectonic stresses, cause a sharp build-up of pressures in the water and gases that are trapped within the sedimentary rock,’ says University of Adelaide geologist Mark Tingay.
‘A mud volcano forms when the fluid pressures become large enough to fracture the overlying rocks that are sealing these intense pressures, allowing the muds and gases to erupt to the surface.’
Images from NASA’s Landsat show the island has been gradually receding over the last few years since it first came to be.
Trails of mud and sediment seen in the images indicate it was steadily dwindling, as waves and tides eroded the structure.
According to NASA, the island barely breached the waterline by the end of 2016.
And, by the time spring came this year, it could no longer be seen above the surface at all.
‘Zalzala Koh may be out of sight for now, but that does not mean it is completely gone,’ NASA says.
‘In 2019, hints of the island persist in Landsat imagery.’
Just last month, for example, the satellite imaged trails of sediment around the island’s submerged base, the space agency notes.