Friday, 11 May 2018

Hawaii: A Slow Emergency

Hawaii: A Slow Emergency and a Sudden Cliff Slump Disaster, Megatsunami




This becomes obvious in Figure 2. It shows how the permanent GPS stations installed and operated by the Hawaii Volcano Observatory moved in response to the 6.9 quake. The red arrows indicate the direction of horizontal motion and all of them point to the southeast. The length of each arrow represents the extent of the motion with the longest ones having moved by more than 2 feet.


Hawaii's Kilauea volcano could be ready to blow, scientists say


10 May, 2018


Geologists warned Wednesday that Hawaii’s Kilauea volcano could soon experience explosive eruptions from its summit and launch large rocks and ash into the air.

The threat of explosive activity will rise as lava drains from the summit of Kilauea, one of the most active volcanoes in the world, and explosions will be possible in the coming weeks if the lava dips below the groundwater table, the U.S. Geological Survey (USGS) said.
If lava drops below the groundwater level, it could heat up the water and create steam. The steam could build in pressure as rocks fall and form a dam within the volcano’s walls and "cause steam-driven explosions" with "very little warning,” the Hawaiian Volcano Observatory (HVO) told the Honolulu Star-Advertiser.

The volcano could then eject "ballistic rocks" of lava up to several feet in diameter, the USGS said. It may also send pebbles shooting into the air several miles away.

"Debris expelled during such explosions could impact the area surrounding Halemaʻumaʻu and the Kīlauea summit," the HVO told the Star-Advertiser.

There could also be potential for ash and sulfur dioxide emissions. Ash can cause eye and breathing irritation, reduce visibility and interfere with electrical lines, the Los Angeles Times reported.

So far, the eruption has destroyed 36 structures since it began releasing lava from fissures that opened in a Big Island neighborhood about 25 miles east of the summit crater. A 15th vent opened Wednesday, spreading lava through Leilani Estates and neighboring Lanipuna Gardens, Hawaii officials said.

Two more fissures open up on Big Island. William La Jeunesse reports from Hawaii.
Separately, Hawaii Gov. David Ige said the Puna Geothermal Venture energy plant near the lava outbreak was accelerating its removal of about 50,000 gallons of stored pentane, a flammable gas, from the site.

It would be "very, very hazardous" if a volcanic vent were to open under the facility where the fuel is stored, the governor said. He expected it would all be removed by Thursday.

The explosive conditions resembled Kilauea’s 1924 summit eruption that killed one person and spewed rocks, ash and dust into the air for 17 days, said Tina Neal, scientist-in-charge at the USGS Hawaiian Volcanoes Observatory.

Steam and gas rise from Kilauea's summit crater in Volcanoes National Park, Hawaii, Wednesday, May 9, 2018. Geologists warned Wednesday that Hawaii's Kilauea volcano could erupt explosively and send boulders, rocks and ash into the air around its summit in the coming weeks. (AP Photo/Jae C. Hong)
Steam and gas rise from Kilauea's summit crater in Volcanoes National Park, Hawaii on Wednesday. (Associated Press)

No one lives in the immediate area of the summit crater. But people have continued to visit Hawaii Volcanoes National Park, which includes the crater and surrounding region. The park will be evacuated before conditions worsen, officials said.

Nearly 2,000 residents have been ordered to evacuate the neighborhoods close to the vents, but some ignored the order and remained to watch over their property. Authorities went door-to-door in Lanipuna to get people out of their homes Tuesday.






The Science Behind Hawaii's Erupting Volcano


10 May, 2018

Hawaii’s Kilauea volcano has entered a new destructive period of eruptions, which has happened several times since it resumed producing lava in 1983. Here’s some context behind one of the world’s most active volcanoes:

Kilauea is mass building


Kilauea is currently in the second phase of growth, the “shield building” stage, where it is the most active and the most voluminous.
1. Pre-shield
Small eruptions below sea level.
2. Shield building
Volcanic mass grows above sea.
3. Post-shield
Magma cap flows, covers volcano.
" 
In this stage, occurrences of lava flows and eruptions alternate. This can continue up to 2 million years.
 
Lava flows in past 1,000 years. Kilauea is covered with 90% young flows.

Beneath Kilauea


Lava eruptions have occurred at the volcano’s summit since 2008 and since 1983 on its eastern shoulder at a crater called Pu'u O'o, which collapsed on April 30, and sent lava searching for a new path downhill.
 


The cycle of volcanic eruptions and hazards


Scientists are concerned that if the lava column drops to the level of groundwater beneath Kilauea summit, it will cause more eruptions.
 
1. Magma column drops to water level.
Normally, when the lava lake level is high, temperatures are so hot that the groundwater in surrounding rocks is kept away from the magma.
2. Groundwater interacts with hot rock.
When lava meets the water, steam is created. Rocks can fall from walls as the lava lake lowers, and form a dam holding back steam.
3. Steam pressure builds, then explodes.
Rocks of up to 12 tons can shoot out of the volcano to a distance of half a mile. Marble-size rocks can fall for several miles, while falling ash is a concern 10 to 20 miles downwind.

Hawaii Island’s five volcanoes


Hawaii Island is made up of five volcanoes, four of which are considered active. Kohala is the oldest volcano on the island and inactive.
 
Sources: USGS, Smithsonian Institution, National Park Service


From yesterday - 


WITHIN THE PAST FEW MINUTES, THERE HAS BEEN A TREMENDOUS EXPLOSION AT THE KILAUEA VOLCANO IN HAWAII.

Earlier today, the lava lake in the main crater of the erupting Kilauea Volcano on the big island of Hawaii virtually disappeared; sinking so low it could not be seen.

People thought this was a good sign, but it wasn't. When the lava level dropped, it allowed water from the sea to come backwards through the lava tunnels and directly into the volcano. This has now caused a Phreatic Eruption!

A phreatic eruption, also called a phreatic explosion, ultravulcanian eruption or steam-blast eruption, occurs when magma heats ground or surface water. The extreme temperature of the magma (anywhere from 500 to 1,170 °C (932 to 2,138 °F)) causes near-instantaneous evaporation to steam, resulting in an explosion of steam, water, ash, rock, and volcanic bombs.

At Mount St. Helens, hundreds of steam explosions preceded a 1980 plinian eruption of the volcano.

The fact this has now taken place is a deadly bad sign of worse to come. Prior to this taking place, just MINUTES AGO, new volcanic fissures were opening in new places miles away from the volcano indicating things are getting much worse, not better.

If Kilauea Violently erupts, an unstable landmass called the Hilina slump, which is 10 miles wide by 15 miles long and several miles deep, is expected to fall off the sea-side of the volcano into the Pacific Ocean. Such a slide would instantly generate s Pacific-wide TSUNAMI which would wipe out cities on the US West Coast within four to five hours after it took place.

Waves projected at 30+ Meters high (90+ feet tall) would inundate San Diego, Los Angeles and other large cities, wiping much of them off the face of the earth. (Full explanation HERE)

This is a very dynamic situation and people along the US west coast must pay very close attention to the events taking place in Hawaii.


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