The partial collapse of a crater wall caused an explosion and eruption Sunday at Hawaii’s Kilauea volcano.

The U.S. Geological Survey’s Hawaiian Volcano Observatory said that the small explosion spread lava and debris around the rim of the Halemaumau Crater.  USGS geologist Janet Babb compared the blast to striking the top of a bottle of champagne.

“You look at the bottle and you see the liquid, but you don’t see the gas,” she said. “There’s a lot of gas in the lava. And so, when that rock fall hits the lava lake, it’s like the moment you knock the top of the champagne bottle off and that gas is released and it hurls molten lava and rock fragments.”

Babb said the small eruption sent rocks flying about 280 feet into the air.

The lava lake had reached record levels last week, reaching a point where it could be seen from an observation deck for the first time since its construction.  The explosion was the first time that a lake similar to his one has been seen since 1974.

USGS scientists say the vent within the Halemaumau Crater has been rising and falling since it first opened.  A 3.6 magnitude earthquake struck the area Monday morning.