Cracks here in Polyvotis crater, and elsewhere along the main faults in the caldera, could have been caused by deformation through magma intrusion below the island. In modern times, Nisyros showed significant ground deformation between 1996 and 1998. Uplift of 14 cm was recorded, which was partly interpreted as the elastic response of the shallow volcanic edifice to the inflation of a magma chamber. A ground rupture 600 m in length formed in the caldera floor between 2001 and 2002 and another in 2011. Those ruptures have been attributed to stress release along existing faults, sub-surface erosion or magma intrusion; they could be a result of a combination of any or all of them.
Cracks here in Polyvotis crater, and elsewhere along the main faults in the caldera, could have been caused by deformation through magma intrusion below the island. In modern times, Nisyros showed significant ground deformation between 1996 and 1998. Uplift of 14 cm was recorded, which was partly interpreted as the elastic response of the shallow volcanic edifice to the inflation of a magma chamber. A ground rupture 600 m in length formed in the caldera floor between 2001 and 2002 and another in 2011. Those ruptures have been attributed to stress release along existing faults, sub-surface erosion or magma intrusion; they could be a result of a combination of any or all of them.
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