Monday, July 22, 2019

Ubinas Volcano Eruption In Peru: State Of Emergency, Mass Evacuations, Future Quakes For California?




A state of emergency has been declared in the area around the volcano after it violently exploded on July 20, 2019, sending ash all the way into Bolivia.

Nearly 30,000 people have been evacuated.

According to Peru’s National Emergency Operations Center (COEN), ash from the volcano has covered 617 schools and 20 health centers in the southern region of the Andean nation.

The volcano set off a series of explosions last Thursday and emitted a column of ash about 5 kilometers (3 miles) high, which has since drifted with the wind, taking with it toxic gases.

The Geophysical Institute of Peru (IGP) issued an ongoing “orange warning” on Sunday, indicating further moderate explosions with more ash emission possible.
The majority of those affected by the eruption — 19,000 of the 29,700 — live in the area bordering Bolivia to the east. About 9,000 people to the south, around the town of Moquegua, have also been affected since the volcano erupted last week.

A state of emergency was declared by President Martin Vizcarra after he visited the area in order to accelerate distribution of aid, and speed up evacuations of communities.





The San Andreas fault is about to rupture and here’s what will happen when it does


The director of the Southern California Earthquake Center, Thomas Jordan, made an announcement recently that would have sent a chill down the spine of every Californian<.

The San Andreas fault appears to be in a critical state and as such, could generate a large earthquake imminently.

Of course, the reiteration of the seismic hazard to Californians will be nothing surprising, but what is new is the warning that the southern portion of the fault “looks like it’s locked, loaded and ready to go”.


Why is this eminent seismologist making these alarming statements?

Well, the fact is that there has not been a major release of stresses in the southern portion of the San Andreas fault system since 1857. In simple terms, the San Andreas is one of many fault systems roughly marking the border between the Pacific and North American tectonic plates. Both plates are moving in an approximately northerly direction but the Pacific plate is moving faster than its North American counterpart, meaning that stresses between the plates are constantly building up.
In 1906, some of these stresses were catastrophically released in the San Francisco Bay area in a 7.8 magnitude event and again, in northern California, during the 6.9 magnitude 1989 Loma Prieta earthquake. Events of these magnitudes, however, have not occurred along the San Andreas fault in the south of the state – the 1994 Northridge event was associated with a nearby, but separate, fault system – leading to the suggestion that one is imminent and, given the amount of stress that might actually have accumulated, when it arrives it will be the “Big One”.
...recent predictions limit the possible maximum earthquake magnitude along the San Andreas fault system to 8.0, although with a 7% probability estimate that such an event could occur in Southern California in the next 30 years; over the same period, there is a 75% chance of a magnitude 7.0 event. While magnitudes of 7.0, 8.0 and 9.0 might sound negligibly different, the energy that such events would unleash varies significantly, with a magnitude 9.0 event releasing 32 times more energy than a magnitude 8.0 and 1,000 times more energy than a magnitude 7.0.

What is realistic, however, is that a great amount of destruction is likely. While the building codes in California are stringent, recommending retrofitting of seismic protection measures to older buildings and preventing the construction of new buildings near to known fault lines, there is no way to make a building 100% safe.

Even so, in all probability, the San Andreas is likely to generate a significant earthquake in the not too distant future. When it arrives, the damage will be significant and southern California will be massively affected. But Californians are no strangers to these events and the infrastructure of the state, in recent times, has been designed with earthquake protection in mind.



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