Ongoing volcanic activity creates sinkholes and cracks throughout Hawai‘i Volcanoes National Park

Much of Hawai’i Volcanoes National Park has been closed for three months due to hazards caused by frequent earthquakes triggered by collapse events at the summit of Kīlauea Volcano. Although seismicity decreased over the weekend, the temblors – more than 18,000 in the last 30 days – have wreaked havoc throughout the park. Those magnitude 5.0 and higher riddle Highway 11, other park roads, overlooks and trails with dangerous sinkholes and cracks. Jaggar Museum and the USGS Hawaiian Volcano Observatory buildings are damaged and stand empty.The summit crater, Halema’uma’u, has more than quadrupled in size as magma drains out to the lower East Rift Zone eruption outside the park.
The new dimensions are staggering to those familiar with Halema’uma’u. Once 280 feet deep, it is now more than 1,500 feet deep in places. Its volume has increased to 800,000,000 cubic meters, according to USGS, an amount equivalent to about 300,000 Olympic-sized swimming pools.
Without lava pressure supporting the summit, large and sudden collapses reshape Hawai’i Volcanoes National Park. More than 60 large collapse/explosion events have occurred since the park closed on May 11.

Cracks have formed on different viewpoints across the National Park. Picture via USGS

The earthquakes also increase the risk of fire: broken waterlines have left most of the park without running water for fire suppression. Fixing them makes little sense as long as the earthquakes continue. Scientists say the activity could last months, even years.
Only when the destructive earthquakes subside will the park be able to fully assess damages, clean up the mess and develop a strategy to reopen.

Dangerous rock slides have reached famous trails. Picture via USGS

Large sinkholes and fractured asphalt on Highway 11 are being repaired by state highway workers, often necessitating one-lane closures and a reduced 25 mph speed limit.

And roads have started being swallowed by sinkholes. Picture via USGS

Government agencies are working together to create alternate and emergency routes should the highway fail. But the fate of park features like Thurston Lava Tube are unknown because it’s too risky to send anyone inside to take a look.
After more than three months, the volcanic eruption on Hawaii’s Big Island appears to be slowing. Geologists at the Hawaiian Volcanic Observatory say the flow of lava from a crack in the earth at the foot of the Kilauea volcano has greatly diminished in recent days. It was lava from that vent, Fissure 8, that ran toward the coast in a molten river, inundating two seaside communities and reshaping the island’s southeast coast. That doesn’t mean the event is over. Tina Neal, the scientist in charge of the observatory, noted that eruptions like this typically wax and wane:

While scientists cannot predict exactly when the eruptive and seismic activity will end, Hawai’i Volcanoes National Park invites everyone to explore how a volcanic landscape snaps back to life.

http://strangesounds.org/2018/08/ongoing-volcanic-activity-creates-sinkholes-and-cracks-throughout-hawaii-volcanoes-national-park.html