Image
Very strong M7.3 earthquake hits Venezuela at intermediate depth
A very strong earthquake registered by the USGS as M7.3 hit near the coast of Sucre, Venezuela at 21:31 UTC on August 21, 2018. The agency is reporting a depth of 123.2 km (76.5 km). EMSC is reporting M7.3 at a depth of 112 km (69.6 miles). According to the USGS, the epicenter was located  20.9 km (13.0 miles) NNW of Yaguaraparo, 38.4 km (23.9 miles) ENE of Carúpano (population 112 082), 69.4 km (43.1 miles) WNW of Güiria (population 40 000), 107.6 km (66.9 miles) ESE Porlamar (population 87 120) and 109.1 km (67.8 miles) ESE of La Asunción (population  35 084), Venezuela. There are 560 000 people living within 100 km (62 miles). Based on all available data, there is no tsunami threat, PTWC said. Some 52 000 people are estimated to have felt very strong shaking, 2 089 000 strong, 2 587 000 moderate and 3 928 000 light. Buildings were evacuated in the capital Caracas and people fled homes. Shaking was felt as far away as …

Washington state's Mount St. Helens volcano hit by 89 Earthquakes so far this year

Image result for Mount St. Helens

Mt. St. Helens, the source of the deadliest volcanic eruption in US history – and only 500 km south of Vancouver – is back.
According to a search of the US Geological Survey records, there have been at least 89 earthquakes under or near the volcano this year.
The largest quake so far has been a 3.9 magnitude, a few kilometers northeast, but the vast majority of the others have all been less than 1 magnitude in force.
mt st helens earthquake

When St. Helens is ready to erupt, ‘we will know’

Seth Moran, Scientist-in-Charge at the USGS Cascades Volcano Observatory, told Daily Hive it’s not unusual that earthquakes happen right at the volcano.
“Those occur continuously but there are ebbs and flows, and about a month ago we started getting a little uptick,” he said.
Moran said it was the 3.9 magnitude earthquake, which occurred 12 km northeast of the volcano, that was different.
“[This] was the second largest earthquake we’ve seen in the Mt. St. Helens area since 1981,” said Moran. “And it was followed by a vigorous, but short-lived, aftershock sequence.”
Moran says the earthquakes at the volcano and those further northeast are happening for different reasons.
“The earthquakes at St. Helens are pretty clearly reflecting magmatic processes that are ongoing, at the volcano or beneath the volcano,” he said.
“There’s probably a little bit of magma coming in and the system is recharging and getting ready for the next eruption, which we think is years and decades down the road.”
Moran said the earthquakes to the northeast are likely more regular, tectonic earthquakes as happens in western Oregon, British Columbia, and Washington.
“There’s no question that once St. Helens is actually ready to erupt, we will know. It’s been very clear the two times it’s erupted, in 1980 and 2004,” he said.
“[There’ll be] lots of earthquakes, bigger than what we’re seeing right now, and you start to see other signs, like deformation at the surface, and an increase in gas coming out of the volcano.”

Mt. St. Helens eruption deadliest in US history

So Mt. St. Helens is not expected to erupt anytime soon – but when it does, it is a serious force to be reckoned with.
In 1980, there was a 4.2 magnitude earthquake near Mt. St. Helens. The volcano began venting steam and its north face began to bulge.
Shortly afterward, a 5.1 magnitude quake caused the north face to collapse, in the largest known debris avalanche in history.
The magma that erupted covered more than 600 square kilometers and more than 1.5 million metric tons of sulfur dioxide were released.
All this created volcanic mudflows which traveled 27 km, destroying bridges and work camps, and for nine hours ash erupted reaching 27 km above sea level.
Ash from the eruption traveled as far as Edmonton in Alberta.
mt st helens earthquake
Overall, the 1980 Mt. St. Helens eruption killed 57 people, nearly 7,000 deer, elk, and bears, and an estimated 12 million fish from a hatchery.
It was the deadliest volcanic eruption in US history.
The Mt. St. Helens eruption also destroyed or damaged more than 200 homes, almost 300 km of highway and 24 km of railways.

Popular posts from this blog