Geology, Earthquakes & Volcanism News and Discussions

[Time_Traveller]

This thread covers Earthquakes and volcanoes and disasters which can have enormous global consequences and can change the course of history. It will be a discussion on current seismic/volcanic hazards, risks of future hazards, preparedness and other scientific things.

YVO’s 2021 field season is underway!

May 17, 2021

For half the year, Yellowstone is largely inaccessible to geologists, buried under snow and ice and subject to fierce storms. By May, however, improved weather and melting snow opens the park to field work. The 2021 field season promises to be a productive one for the Yellowstone Volcano Observatory.

Yellowstone Caldera Chronicles is a weekly column written by scientists and collaborators of the Yellowstone Volcano Observatory. This week's contribution is from Michael Poland, geophysicist with the U.S. Geological Survey and Scientist-in-Charge of the Yellowstone Volcano Observatory.

This past week saw the some of the first field work of the year by Yellowstone Volcano Observatory (YVO) scientists in Yellowstone National Park. The opening of the 2021 field season provides an opportunity to preview YVO’s plans for the next few months, before the snow starts accumulating once again and the field season ends in November.

Over the past several days, geophysicists installed about 15 semipermanent GPS stations around the park. These are low-profile sites that run on battery power with a small solar panel but that are not telemetered, so the data cannot be downloaded via radio. For the past 14 years the stations have been set up every May and picked up every October before they are snowed in, and the data downloaded and processed upon return to the office . The data aren’t useful for real-time monitoring, but they densify the existing continuous GPS network and can help scientists better understand processes like past episodes of uplift at Norris Geyser Basin.

https://www.usgs.gov/center-news/yvo-s- ... e_products

[wjfox]

Science drill ship sets depth record off Japan

1 day ago

A new deep-ocean record has been set for a scientific drilling operation.

Researchers working off the coast of Japan lowered a giant piston corer through more than 8km of water in order to pull sediments from the seabed.

It took two hours and 40 minutes simply for the equipment to descend into position above the ocean floor.

The drilling exercise, mounted from the Research Vessel Kaimei, is part of a project to read the history of great earthquakes in the region.

The chosen core site in the Japan Trench is very close to the epicentre of the Magnitude 9.1, Tohoku-oki event in 2011, which also produced a tsunami that devastated communities on the nation's eastern seaboard, and knocked out the Fukushima nuclear plant.

The 37m of sediment retrieved by the piston corer will hopefully preserve details of much older quakes - those that occurred before any written accounts.

https://www.bbc.co.uk/news/science-environment-57172348

[Time_Traveller]

Second earthquake shakes China; 1 dead in earlier quake

14 hours ago

The U.S. Geological Survey says a second earthquake has hit China

A 7.3-magnitude quake hit Southern Qinghai, China early Saturday. The quake was centered about 10 kilometers (6 miles) deep in central China, about 1,000 kilometers (621 miles) north of an earlier quake.

USGS geophysicist Jonathan Tytell said the agency expects “significant economic losses” and damage from the quake, but that it's centered in a mostly rural area. There were no immediate reports of deaths.

On Friday night, another strong, shallow earthquake shook an area of southwestern China near Myanmar causing at least one death.

The two quakes were not related, Tytell said.

https://www.independent.co.uk/news/seco ... 51962.html

[wjfox]

Mount Nyiragongo: DR Congo residents flee as volcano erupts

1 hour ago

Thousands of people have fled their homes in the Democratic Republic of Congo after a large volcano erupted.

Fountains of high lava burst from Mount Nyiragongo into the night sky forming a thick red cloud over the town of Goma, which has a population of two million.

The lava flow reached the city's airport but has reportedly now stopped.

The volcano, located 10km (six miles) from Goma, last erupted in 2002 killing 250 people and making 120,000 homeless.

During the early hours of Sunday, many residents headed across the nearby Rwandan border, while others went to higher grounds to the west of the city.

https://www.bbc.co.uk/news/world-africa-57215690

[weatheriscool]

Intense earthquake swarm near Salton Sea, Southern California

https://watchers.news/2021/06/05/intens ... alifornia/

Intense earthquake swarm near Salton Sea, Southern California

An intense earthquake swarm is taking place near the Salton Sea in Southern California, U.S. on June 5, 2021, starting with M2.2 at 08:05 UTC (01:05 LT).

The USGS has registered 285 earthquakes by 21:24 UTC. The swarm is still in progress and new earthquakes are being registered every few minutes, sometimes 2 or 3 within 1 minute.

The strongest so far was M5.3 at 17:55 UTC (10:55 LT). The quake struck 11 km (7 miles) W of Calipatria and 11 km N of Westmorland at a depth of 5.8 km (4.6 miles).

3 000 people are estimated to have felt strong shaking, 9 000 moderate, and 201 000 light.

More than 1 050 people submitted 'I felt it' reports.

[weatheriscool]

A new approach to calculate earthquake slip distributions
https://phys.org/news/2021-06-approach-earthquake.html
by Morgan Rehnberg, American Geophysical Union

During an earthquake, Earth's crust moves, or slips, along fractures in rock called faults. These movements can be detected and recorded by geophysical instruments located at various locations on Earth's surface. Recordings from geophysical instruments have a different orientation relative to the earthquake's epicenter and therefore record a different aspect of a fault slip. An important problem in seismology is reconciling these different measurements to determine the true orientation of an earthquake's many fault slips, as well as the large-scale stresses that create them.

The process of determining the distribution of fault slips that creates a given set of geophysical observations is called slip inversion. In the computer era, it has traditionally been accomplished by a variety of least squares fitting routines that attempt to match possible slip distributions to the observed data. However, this technique faces a number of challenges, including ensuring a physically plausible solution, properly handling complex observational uncertainties, and determining a slip distribution that varies spatially.

[caltrek]

What Does It Take for a Volcano to Blow?
by Daniel Conrad
June 22, 2021

https://www.courthousenews.com/what-doe ... o-to-blow/

Introduction:

(Courthouse News) Though the world’s oldest volcanoes erupt infrequently, those eruptions are larger and more dangerous than younger volcanoes’ emissions, according to a new review of the scientific literature on volcanic activity that reveals the how and why of our planet’s most explosive events.

The paper, published Tuesday in the scientific journal Nature Reviews Earth and Environment, contributes to scientists’ quest to accurately predict when volcanoes will blow, how frequently they will erupt and how dangerous these eruptions will be — knowledge that would come as a great help for the 800 million humans around the world who live near active volcanoes.

Most magma — the molten hot rock that flows like a fluid miles below the Earth’s surface — does not finish its journey from the inner earth to the planet’s surface, the researchers wrote.

“During its journey, magma can get trapped in reservoirs within the Earth’s crust, where it may stagnate for thousands of years and potentially never erupt,” said Meredith Townsend, an earth scientist at the University of Oregon who participated in the research, in a statement to the press.

Magma is called lava when it flows out from the planet’s depths and reaches the air, which cools the lava into “extrusive” igneous rocks such as basalt, obsidian and pumice.

For at least two millennia, small explosions have taken place about every 10 minutes at the Stromboli volcano north of Sicily.
(Photo by Luca Caricchi, UNIGE)

[caltrek]

Philippine Government Orders Evacuation as Volcano Taal Alert Level is Raised
July 1, 2021

https://www.msn.com/en-us/news/world/ph ... uxbndlbing

Introduction:

(MSN) Authorities in the Philippines have started evacuating thousands of people after the alert status was raised on Thursday for a restive volcano that spewed a kilometre-high (0.62-mile) plume of gas and steam.

The alert for the Taal volcano, approximately 70km (45 miles) south of central Manila, moved from level 2 to level 3 on the 5-level scale, which the seismology and volcanology agency said meant a “magmatic intrusion” at the main crater “could further drive succeeding eruptions”.

Taal is one of the world’s smallest active volcanoes. Despite standing at only 311 metres (1,020 feet), it can be deadly and an eruption in 1911 killed more than 1,300 people.

In January last year, Taal shot a column of ash and steam as high as 15km (9.3 miles) into the sky, which forced more than 100,000 people to abandon their homes, causing widespread flight cancellations and heavy ash falls in Manila.

Authorities have warned that the current eruption could potentially be more hazardous than that of last year.

[weatheriscool]

5.2 quake on Hawaii's Big Island felt as far away as Kauai
Source: AP

By CALEB JONES

HONOLULU (AP) — A magnitude 5.2 earthquake has hit off Hawaii’s Big Island.

According to the U.S. Geological Survey, the quake hit less than 3 miles (5 kilometers) offshore of the northwest coast of the Big Island Monday. The earthquake was about 17 miles (27 kilometers) below sea level.

The epicenter was about 75 miles (120 kilometers) north of both Hilo and Kailua-Kona.

The USGS said people reported feeling some light shaking as far away as Kauai with strong shaking near the center on the Big Island. Shaking was reported on all the main Hawaiian Islands.

Read more: https://apnews.com/article/hi-state-wir ... a022e9f4d3

[weatheriscool]

Magnitude 6.2 earthquake strikes central California
Share

A magnitude 6.2 earthquake struck central California on Thursday, the European-Mediterranean Seismological Centre (EMSC) said.

The quake had a depth of 10 kms (6.21 miles). There have been no reports of injuries or damages so far.

https://www.israelnationalnews.com/News ... spx/546261

[Time_Traveller]

The Croatian village where the land became 'Swiss cheese'

5th July 2021

Villagers in north-east Croatia feared their homes might be swallowed when almost 100 enormous sinkholes appeared in a month. Now scientists are trying to understand if the land that is left is safe.

It happened suddenly and without warning. Where there should have been the emerging first shoots of potato seedlings behind the orchard in Nikola Borojević's spacious garden, there was now huge hole. Measuring 30m (98ft) wide and 15m (49ft) deep, it quickly filled with water. And it wasn't the only one.

Within the space of a few weeks, dozens of similar holes had opened up around the village of Mečenčani and neighbouring Borojovići in north-east Croatia. The one outside Borojević's home in Mečenčani appeared on 5 January, just six days after a 6.4 magnitude earthquake struck the area around the nearby city of Petrinja. It was the strongest earthquake to have hit Croatia for more than four decades, killing seven people and destroying thousands of homes.

While landslides and sinkholes are known to be triggered by earthquakes, along with other strange geological phenomena such as liquefactions – where the solid ground begins to behave like a liquid – the sheer number of holes appearing around the two villages surprised and baffled experts. A month after the earthquake, there were almost 100 sinkholes spread over a 10 sq km (3.8 sq miles) area, with new ones opening every week.

The hole in Borojević's garden is now the largest in the area. When it first appeared it was 10m (33ft) wide, but started to grow almost immediately.

https://www.bbc.com/future/article/2021 ... -sinkholes

[caltrek]

Largest U.S. Earthquake in 50 years: What We Know So Far

https://earthquake.alaska.edu/

Introduiction:

Alaska Earthquake Center) At 10:15pm Alaska time on July 28, a magnitude 8.2 earthquake struck offshore of the Alaska Peninsula, the largest U.S. earthquake in 50 years. The Chignik Earthquake depth was approximately 28.5 miles, an intermediate-depth earthquake.

The Chignik Earthquake occurred relatively close (about 45 miles) to the location of the M7.6 Simeonof Island Earthquake that ruptured July 21, 2020. The Chignik Earthquake seems to be related to the earlier earthquake; both occurred along the interface between the subducting Pacific and overriding North America plates, although the Chignik Earthquake was the deeper of the two. The Alaska Peninsula is a seismically active region where thousands of earthquakes occur each year. The largest earthquakes are located along the interface, which is called the Aleutian megathrust. The M8.2 event ruptured this interface in the region between the Shumagin Islands to southwest and Kodiak Island to northeast. Previously, the 1938 M8.3 earthquake ruptured this section of the interface.

[weatheriscool]

Magnitude 8.2 earthquake hits off Alaska coast
A bit of a shaker, no damage reported:
https://www.adn.com/alaska-news/2021/07 ... arthquake/
Gulf of Alaska coast under tsunami warning following 8.2 earthquake - Anchorage Daily News

[Xyls]

Magnitude 7.2 earthquake strikes Haiti

This is a larger quake than the 2010 Earthquake that killed north of 100,000+ people.

https://www.cnn.com/world/live-news/hai ... index.html

More details expected.

[weatheriscool]

Earthquake of magnitude 7 strikes Alaska peninsula - EMSC
Source: Reuters

Aug 14 (Reuters) - An earthquake of magnitude 7 struck the Alaska peninsula, the European-Mediterranean Seismological Centre (EMSC) said on Saturday.

The U.S. Tsunami Warning System said there was no tsunami warning after the quake.

The quake was at a depth of 10 km (6 miles), EMSC said.

Read more: https://www.reuters.com/business/enviro ... 021-08-14/

[weatheriscool]

[weatheriscool]

[weatheriscool]

[weatheriscool]

At least 304 dead as Haiti struck by 7.2-magnitude earthquake

At least 304 people have died and hundreds are missing after Haiti was struck by a 7.2-magnitude earthquake that reduced churches, hotels and homes to rubble, in the latest tragedy to hit a Caribbean nation already mired in profound humanitarian and political crises and still reeling from the recent assassination of its president.

The earthquake on Saturday, which struck the country’s south-west at 8.29am local time, was felt across the Caribbean and rekindled painful memories of the devastating 2010 quake that killed more than 200,000 people. The prime minister, Ariel Henry, has declared a month-long state of emergency.
...
The US president, Joe Biden, authorised an immediate response and named Samantha Power as the senior official coordinating the US effort to help Haiti. USAID will help to assess damage and assist in rebuilding, said Biden, who called the United States a “close and enduring friend to the people of Haiti”.

A growing number of countries offered help, including Argentina and Chile, which said it was preparing to send humanitarian aid. “Once again, Haiti has been hit by adversity,” the Chilean president, Sebastián Piñera, said.

https://www.theguardian.com/world/2021/ ... earthquake

[Yuli Ban]