Thousands of earthquakes a year: the US is preparing for the eruption of the largest volcano in the world


The United States Geological Survey (USGS) is urging people to prepare for a possible eruption of the world’s largest volcano: Mauna Loa on the Big Island of Hawaii. WeatherBoy writes about it.


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In a recent news release, scientists at the Hawaiian Volcano Observatory (HVO) from the USGS warned: “While a Mauna Loa eruption is not imminent, now is the time to rethink plans. As with preparing for hurricane season, having a plan in advance helps during an emergency.”

Mauna Loa is considered the largest active volcano on Earth and rises to 13,681 feet (4170 m) above sea level. Mauna Loa rises from the ocean floor in the central Pacific Ocean, from a depth of about 3 miles (4.8 km). Due to the significant mass of the volcano, the ocean floor directly below Mauna Loa is lowered by another 5 miles (8 km). According to the USGS, this places the top of Mauna Loa about 56,000 feet (17,068 m) above its base; a huge volcano covers half of the island of Hawaii, also known as the “Big Island of Hawaii”.

Mauna Loa eruptions tend to produce large, fast-moving lava flows that can affect areas on the east and west sides of the Big Island from Kona to Hilo. On the southern and western sides of the island, Mauna Loa lava flows reached the coast 8 times: in 1859, 1868, 1887, 1926, 1919 and three times in 1950.

Although Mauna Loa is not currently erupting, deformation rates and seismicity remain elevated compared to long-term background levels, according to the USGS. GPS measurements continue to show a slow, long-term rise in upper level pressure consistent with magma feeding into the volcano’s shallow storage system. The slight increase in pressure levels that began in January continues.

Over 225 earthquakes hit Mauna Loa last week. However, most of them had a magnitude of 2.5 or less and were below the top. The strongest earthquake in the last 7 days occurred in Pahala on the afternoon of March 8 – magnitude 4.2. Over 660 earthquakes have occurred on the island of Hawaii in the past 30 days, and over 6,800 in the past 365 days.

As another Mauna Loa eruption is imminent, although the time has yet to be determined, the USGS is urging people in Hawaii to create a personal response plan, prepare a “hiking bag” and determine what to do in the event of an eruption in Hawaii at different times of the day or week. in different places (for example, at work, at school, on the road).

“The most important thing you can do is create a personal response plan,” the service recommends. “Document what you will do if the volcano erupts and make sure your family and friends are aware of the plan.”

The U.S. Geological Survey suggests tidying up your travel bag, which, in addition to essentials, advises you to put important documents such as a birth certificate, documents and medicines, and do not forget a plan to keep in touch with family members and other important people in case of an emergency. situations.

Mauna Loa is one of the 5 volcanoes that make up the Big Island of Hawaii. The oldest volcano is Kohala, which is over a million years old. Kilauea is the youngest, estimated at 300,000-600,000 years old. Mauna Loa is the second oldest volcano on the island, estimated to be around 700,000 years old.

Mauna Loa is a shield volcano with long, wide slopes that drop into the ocean. Lava eruptions from Mauna Loa are very fluid and usually non-explosive. The magma for Mauna Loa and Kilauea, the latter of which has been erupting since December, comes from a hotspot in the center of the Pacific Plate. As the plate slowly drifts, Mauna Loa will eventually move away from the chamber, becoming an extinct volcano in the next 500,000 to 1,000,000 years.

The last eruption of Mauna Loa took place from March 24 to April 15, 1984. Lava overflowed near the summit, and the cracks directed the flows towards Hilo. The streams stopped about 4 miles from the city limits. Since then, the lava has not flowed out any more.

Scientists still do not know when and where the lava will pour out as a result of the next eruption. Previous floods have affected the communities of Puako and Waikoloa Beach on the northwest coast, Kailua Kona and Captain Cook on the west coast, Mylolia and Ocean View on the southwest coast, and Hilo on the east coast. Therefore, the USGS is urging residents across the island to prepare for possible volcanic activity. In addition to the dangers associated with fast-moving lava flows, there can be toxic volcanic gases and volcanic haze, fallout of volcanic debris such as ash or volcanic glass.

Hawaii also does not have a monopoly on volcanic threats in the United States. Mauna Loa is only 16th on the list. Even more dangerous are Mount St. Helens and Mount Rainer in Washington, Redoubt in Alaska, Mount Shasta in California, and Mount Hood and Three Sisters in Oregon.

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