Bulge on Kilauea could portend eruption

HILO, Hawaii – A 3-mile-wide bulge at the top of Kilauea Volcano could signal that it will eventually erupt from its summit.

The volcano lies within Hawaii Volcanoes National Park, a popular tourist destination on the Big Island. Lava has been oozing from vents in the flank of the volcano for years, then tumbling into the sea in a fiery stream that visitors can see.

The bulge is caused by a magma buildup between two and three miles below the surface, said Jim Kauahikaua, head of the Hawaiian Volcano Observatory. The magma could increase pressure until it breaks free through in a fiery explosion.

"Over the decades, some (bulges) result in a summit eruption. Most do not," he said. "We don't see this as an immediate cause for concern."

The observatory doesn't have enough information yet to know what the bulge means and how serious it is, he said.

Kilauea's summit periodically puffs up and then sinks, but this much bulging is uncommon. The bulge has lifted the volcano 4.3 inches since earlier this year. The center is immediately south of Kilauea summit's deepest point at Halemaumau Crater.

Scientists said an eruption may be near if there are multiple earthquakes, signaling that underground pressure was building up enough to break rocks.

There were several earthquakes earlier this year, but they have since tapered off, Kauahikaua said.