Hawaii volcano Kilauea has undergone the single “largest scale collapse” witnessed in recent history, volcanologists at the United States Geological Survey (USGS) revealed.

Kilauea’s volatile crater has lost around 250 million cubic metres of volume since eruptions began on May 3 this year.

The subsiding Halemaumau crater summit has lost the equivalent of 100,000 Olympic-sized swimming pools.

Kilauea’s draining magma chambers are fuelling the summit collapse, the USGS warned on Tuesday, June 19.

Two aerial photographs snapped by USGS scientists reveal the extent of the widening crater in Hawaii Volcanoes National Park.