Tag Archives: Geologists

Alert level raised for Hawaii volcano due to rumbles, quakes

FILE PHOTO: The Mauna Loa volcano on the island of Hawaii is shown in this March 25, 1984 handout photo provided by the U.S. Geological Survey, and released to Reuters on June 19, 2014. U.S. Geological Survey/Handout via Reuters

By Dan Whitcomb

(Reuters) – The Mauna Loa volcano in Hawaii has been hit by at least 50 small earthquakes since October of last year, scientists said on Tuesday, prompting U.S. geologists to raise its alert level to yellow.

An eruption of Mauna Loa, the world’s largest active volcano, did not appear to be imminent. The increased seismic activity indicated a shift in the “shallow magma storage system” under the mountain, the Hawaii Volcano Observatory (HVO) said in an advisory.

“As has happened before, it is possible that current low-level unrest will continue and vary in intensity for many months, or even years without an eruption,” the observatory said. “It is also possible that the current unrest is an early precursor to an eventual eruption. At this time, we cannot determine which of these possibilities is more likely.”

Yellow is the second level on the Hawaii Volcano Observatory’s color-coded alert chart, above green, which is used to indicate “background, non-eruptive state.” Orange signifies a volcano exhibiting “heightened or escalating unrest with increased potential of eruption.” The highest alert level, red, indicates that an eruption is imminent.

“HVO expects that days or weeks prior to an eruption, monitoring instruments will detect signs of an increased potential for eruption,” the observatory said. “However, it is also possible that the time frame to eruption could be shorter – hours to days. All communities on the flanks of the volcano should be prepared.”

The last episode of volcanic activity in Hawaii was a destructive eruption of lava last summer from a series of fissures that opened at the foot of Kilauea Volcano, also on the Big Island.

Kilauea spewed rivers of molten rock that swallowed hundreds of homes before creeping several miles (km) to the ocean, ultimately engulfing two seaside housing developments there.

The property losses from the May-to-August event marked the most destructive eruption event of Kilauea or any other volcano in Hawaii’s recorded history.

Mauna Loa, which takes up more than half of the Big Island, and rises 13,679 feet (4,169 meters) above the Pacific Ocean, last erupted in March and April of 1984, sending a flow of lava within 5 miles (8.05 km) of the city of Hilo.

The volcano has produced voluminous flows of lava that have reached the ocean at least eight times since 1868, and twice its eruptions have destroyed villages, in 1926 and 1950.

(Reporting by Dan Whitcomb; Additional reporting by Steve Gorman; editing by Bill Tarrant and Sandra Maler)

Hawaii volcano eruption slows to virtual halt after more than three months

FILE PHOTO: Lava erupts in Leilani Estates during ongoing eruptions of the Kilauea Volcano in Hawaii, U.S., June 5, 2018. REUTERS/Terray Sylvester

By Steve Gorman

(Reuters) – The destructive lava eruption at the foot of Kilauea Volcano on the Big Island of Hawaii has slowed to a virtual halt in recent days for the first time in over three months, geologists said on Monday, although it was too soon to tell what might happen next.

The lone volcanic fissure that was still active last week has dwindled from a fountain of molten rock to a bubbling pond of lava no longer spilling out of the blackened cone surrounding it, said Tina Neal, chief scientist at the U.S. Geological Survey’s Hawaiian Volcano Observatory.

Levels of sulfur dioxide gas vented from the fissure, located on the lower east flank of Kilauea, about 25 miles (40 km) from its summit crater, have also dropped dramatically, she said.

The subdued activity there coincided with another major collapse in the outer wall of the summit crater last Thursday, followed by a final flurry of earthquakes before the peak of the volcano grew still.

“The system appears to have almost shut down completely over the course of a couple of days,” Neal told reporters on a conference call. She said it was “all consistent with something turning off the spigot to the surface.”

At this point, the volcanic reservoir at the bottom of the summit crater appeared “significantly drained” of magma – the term for molten rock before it erupts – that was feeding the lava vents downslope at the surface.

At the height of Kilauea’s current eruption, which began on May 3, a total of two dozen fissures had opened in the ground at the foot of the volcano, in an area scientists call the lower east rift zone. But only one vent, dubbed Fissure 8, was still active last week.

It was a river of lava from Fissure 8 that had crept eastward to the ocean, engulfing two seaside housing developments before pouring into the Pacific. Hundreds more dwellings have been swallowed closer to the eruption site.

FILE PHOTO: Lava fragments falling from lava fountains at fissure 8 are building a cinder-and-spatter cone around the erupting vent, with the bulk of the fragments falling on the downwind side of the cone as it continues to feed a channelized lava flow that reaches the ocean at Kapoho during ongoing eruptions of the Kilauea Volcano in Hawaii, U.S. June 11, 2018. USGS/Handout via REUTERS

FILE PHOTO: Lava fragments falling from lava fountains at fissure 8 are building a cinder-and-spatter cone around the erupting vent, with the bulk of the fragments falling on the downwind side of the cone as it continues to feed a channelized lava flow that reaches the ocean at Kapoho during ongoing eruptions of the Kilauea Volcano in Hawaii, U.S. June 11, 2018. USGS/Handout via REUTERS

The property losses marked the most destructive eruption event of Kilauea or any other volcano in Hawaii’s recorded history.

Neal said it remains to be seen whether the reduced flow at Fissure 8 will turn out to be a brief pause or an extended lull, or whether other vents will reactivate. A similar 88-day eruption in the lower east rift zone in 1955 was punctuated by one pause of five days and one lasting 16 days, Neal said.

Neal said scientists would be surprised if the summit crater produced any new major eruptions in the near future.

The current shift in volcanic activity happened as Hurricane Hector churned across the Pacific toward Hawaii, with forecasters predicting it would skirt past the southern coast of the Big Island on Wednesday.

Neal said the storm would have no effect on the volcano, except for the possibility of large steam clouds producing “white-out” conditions in areas where heavy rain falls on top of molten lava that has yet to thoroughly cool.

(Reporting by Steve Gorman in Los Angeles; Editing by Paul Tait)

Unusual eruptions at world’s largest active geyser in Yellowstone

FILE PHOTO: The Steamboat Geyser erupts in Yellowstone National Park, Wyoming, June 21, 2011. REUTERS/Jim Urquhart/File Photo

By Jon Herskovitz

(Reuters) – The world’s largest active geyser has erupted three times in the past six weeks at Yellowstone National Park, including once this week, in a pattern that is unusual but not at all indicative of a more destructive volcanic eruption brewing beneath Wyoming, geologists said on Saturday.

Steamboat Geyser, which can shoot water as high as 300 feet (91 meters) into the air, erupted on March 15, April 19 and on Friday. The last time it erupted three times in a year was in 2003, the U.S. Geological Survey’s Yellowstone Volcano Observatory said.

The last time it erupted prior to March was more than three years ago in September 2014.

“There is nothing to indicate that any sort of volcanic eruption is imminent,” Michael Poland, the scientist in charge for the observatory, said in an email.

This year’s eruptions have been smaller than a usual Steamboat eruption, but the two in April were about 10 times larger than an eruption at the park’s famed Old Faithful Geyser in terms on the amount of water discharged, he said.

Geologists have not pinpointed a reason for the latest series of eruptions, but say they could indicate a thermal disturbance in the geyser basin, or that Steamboat may be having smaller eruptions instead of one large.

Since most geysers do not erupt on a regular schedule, “it might just reflect the randomness of geysers,” Poland said.

Only Waimangu Geyser in New Zealand has rocketed to greater heights than Steamboat, but not for more than 100 years, the U.S. National Park Service said.

Yellowstone sits atop a volcano that created a vast crater. Its plateau hosts the world’s most diverse and expansive continental hydrothermal systems, including the multicolored springs, mudpots and geysers for which the park is known.

While the Steamboat eruptions are unusual, what would be far more worrying would be the water in the hydrothermal systems drying up, which could indicate that the super hot magma deep below was making its way to the surface.

“Yellowstone hasn’t had a volcanic eruption for 70,000 years! Geysers erupt all the time,” said Jake Lowenstern, a USGS research geologist who specializes in volcanoes.

(Reporting by Jon Herskovitz; Editing by Daniel Wallis and XX)