ATHENS, Greece - A giant ball of magma is swelling under the picturesque Greek island of Santorini (Thira).
Researchers said that the volcanic island has filled with a similar amount of magma as it did during its last eruption, which lasted from 1939 to 1941.
Santorini, which is called Thira by Greeks, is a popular honeymoon island with dramatic, cliff-hanging white-washed towns immortalized in millions of photographs.
It is also popular with cruise ships.
The Daily Mail reported that the magma is accumulating under the surface of the island, triggering small earthquakes - the first seismic activity in two decades.
“If the present rate of inflation were to continue for a small number of years, the intruded volume would be equivalent to the volumes of previous eruptions,” the researchers wrote, according to Businessweek.
Researchers said that Santorini has helped them understand how magma chambers under the Earth grow.
"Before this work, we didn't really know how the volcano behaved during the periods of time between eruptions," David Pyle, study co-author, told OurAmazingPlanet.
"Now, it looks as though the magma chambers beneath volcanoes like Santorini grow in spurts."
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On top of the threat of an explosion, the researchers said that Santorini has been pushed up eight to 15 centimeters (3 to 6 inches) since the mid-20th century.
There is no imminent eruption researchers wrote, but they said that nothing can be ruled out, stating that it would be unwise to ignore what was happening, said Bloomberg.
In what might be a bad sign, a volcanic eruption on Santorini three millenia ago, wiped out many island villages around the Aegean and destroyed the Minoan civilization in Crete.
The findings were published in the journal Nature Geoscience.