Santorini Volcano eruption in the 1950s
Reports of heavy breathing on the popular Greek isle of Santorini are making headlines again.
Following a surprising swarm of earthquakes in early 2011, Santorini’s volcano drew a rapid breath that has raised the surface of the island by as much as 5.5 inches (14 centimeters). That’s the most significant change the volcano has experienced since 1955, shortly after its last eruption, according to a study published in Nature Geoscience.
The island’s new bout of restlessness is not lost on locals. Michelle Parks of Oxford University’s Department of Earth Sciences, a co-author of the new report, describes her visits to Santorini in 2011:
The tour guides, who visit the volcano several times a day, would update me on changes in the amount of strong smelling gas being released from the summit, or changes in the color of the water in some of the bays around the islands. On one particular day in April 2011, two guides told me they had felt an earthquake while they were on the volcano and that the motion of the ground had actually made them jump. Locals working in restaurants on the main island of Thera became aware of the increase in earthquake activity due to the vibration and clinking of glasses in their bars.
Parks had spotted signs of movement of the Earth’s surface on Santorini in satellite radar images following the earthquake swarm earlier that year, so she and her colleagues then surveyed the island using GPS receivers, which can detect millimeter-scaled movements of the earth’s surface. Their results suggest the swift swelling was due to a massive intrusion of molten rock between January 2011 and April 2012. They estimate that the volume of magma that has accumulated beneath Santorini is somewhere between 10 and 20 million cubic meters.
The question on everyone’s mind, of course, is will it blow?
If the high end of the magma estimate is accurate, that means Santorini has already loaded up roughly half the volume of material known to be belched up during the volcano’s typical dome-forming eruptions. These effusive eruptions are relatively small and frequent. Three of them occurred during the 20th century, the last in 1950.
Santorini is also known to take in rapid breaths of magma before its much more catastrophic explosive eruptions, such as the great eruption of 1650 B.C. that wiped out the Minoan civilization. Not to worry: those catastrophes occur only about once every 10,000 to 30,000 years.
Besides, scientists say Santorini’s tremors have dropped off in the past few months. So for now we can all breath easy. Edited from Volcano Watch: Swift Swelling at Santorini