Strangeness in the Alps

By Strange Sounds
Apr 4, 2021

In the case of the central Alps, the situation is scientifically complex. First, a rapid review of the basics of plate tectonics: Earth is basically a floating ball of slick magma with a thin candy shell of crust around the outside. The crust is broken into large parts, and these parts continue to push into and crunch away at each other.

This causes different things — not just earthquakes and volcanoes, but also continental drift and the consequent destruction and recreation of crust. Deep within the Atlantic Ocean, new ocean floor emerges every day as the two sides are pushed apart. On the other end, ocean floor collides with and is pushed beneath the continental plates.

So imagine filling your bathtub with cold water and then dropping in enough big chunks of ice to fill the surface and then some. The chunks will start to push each other and rise and fall. This is exactly what happens in the crust, and it’s why the Alps are still growing.

It’s called crustal uplift, crustal uprise, tectonic uplift—all terms that refer to the same idea. And after thinking about how Earth’s crust roams and interacts, it’s easy to see why deciding how to measure the height of these mountains is itself a challenging problem.

In this case, any crustal uplift is working against the related up-top phenomenon of erosion. The Alps are, cosmologically speaking, just babies compared to many of the world’s oldest mountain ranges. Because of that, they’re still spiky and jagged, extremely tall, and subject to high rates of erosion at their peaks.

Scientists have long believed the Alps are basically shifting in place like an escalator: uplifted by the crust and eroded from the top at the same rate. They can use chemical signatures made by bouncing cosmic radiation to estimate how much of what’s visible at the very top of a mountain is very old and, therefore, the result of erosion of the newer rock over top—like the shiny nose on a much-beloved local statue rubbed for good luck.

“As cosmic rays hit Earth’s surface, oxygen atoms that constitute quartz minerals experience a nuclear reaction,” scientists from Bern University explain in a statement. “[A] new isotope is formed. Because [it’s] only formed on Earth’s uppermost surface, the surface age can be determined with this isotope. If the concentration is high, then the surface has been exposed to cosmic rays for a relatively long time and is therefore relatively old.”

The scientists found that erosion is slower than crustal uplift, especially in Switzerland, where the Alps erode at an astonishing 14 millimeters per 1,000 years. Uplift, on the other hand, can be as high as 800 millimeters during the same time frame. These parts of the Alps are racing upward more than 50 times faster than they’re sanded down.

Understanding the difference can help scientists make more accurate measurements of other phenomena, including in detailed studies of why and where erosion happens the most. More Information Here!!

Ready for a new nightmare scenario? The highly dangerous Cascadia Subduction Zone is linked to the overdue San Andreas Fault and both could trigger a Megaquake along the US West Coast

Read More!!

By Strange Sounds
Dec 7, 2019

And now a relatively new earthquake research sounds like a B movie plot.

It indeed argues that two of the west coast’s biggest earthquake faults may have far more interaction than previously thought.

According to geologists, an earthquake on the Cascadia Subduction Zone could trigger a similar shaker on the San Andreas fault to the south and thus create a giant seismic event along the U.S. West Coast.

Both dangerous earthquake zones are overdue for a big and deadly one.

A nightmare scenario

By Strange Sounds
Dec 7, 2019
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A great earthquake along the Pacific Northwest’s offshore Cascadia fault triggers another great earthquake on the northern San Andreas Fault.

In what may be a case where science catches up to the fertile imaginations of Hollywood script writers, attendees at a major earth science meeting in San Francisco will hear evidence that this cascade of disaster happened many times over the past couple of millennia.

“I mean, Cascadia is big enough by itself,” said Goldfinger, a professor of geology and geophysics at the university. “But if you add in San Francisco and the North Coast, it is literally almost a grade B movie scenario that people don’t want to think about that much.”

Yes, a major quake from the offshore Cascadia subduction zone could trigger California’s famous San Andreas Fault. And those are two of the most dangerous seismic regions in the U.S.

An Active Link Between Cascadia and San Andreas

By Strange Sounds
Dec 7, 2019
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Goldfinger has been studying the Cascadia Subduction Zone for years. The fault runs roughly 600 miles off the west coast, from northern California to British Columbia, where several smaller tectonic plates are sliding under the much larger North American Plate. That subduction zone is capable of producing earthquakes with devastating destructive potential, up to magnitude 9.0.

The San Andreas fault, by contrast, runs about 750 miles under the northern California coast and parts of inland southern California. It is easily the world’s most infamous fault, responsible for the 1906 earthquake that leveled large parts of San Francisco and the Loma Prieta that shook the same region in 1989.

Unlike the Cascadia Subduction Zone, where plates are sliding under one another, the San Andreas Fault is known as a transform fault, the tectonic plates are moving laterally, sliding past each other.

The two faults meet in an area known as the Mendocino Triple Junction. Now, Goldfinger has found evidence that a quake on one could trigger a quake on the other, in essence making for one giant seismic event that would span the entire west coast of the U.S.

The new results stem from the analysis of sediment cores from the Mendocino Triple Junction area. Those cores, pulled from canyons on the ocean floor, show evidence of earthquakes in the form of underwater landslides. Using carbon dating, Goldfinger found that nearly a dozen earthquakes occurred throughout history on both faults at the same time.

Moreover, the analysis found no evidence for the stress transfer working in reverse – from south to north.

Well, when you have two big faults that connect directly, there’s a pretty high probability they’re going to interact in some way. So one fault triggering another, or even becoming synchronized with the other for a period of time, is not a fantastical scenario. It is actually a fairly likely scenario. It just isn’t on the radar anywhere yet.

But it’s not so common to have linkage across two different kinds of faults, from a subduction zone onto a strike-slip fault. So this is new and interesting.

Video: Earthquake In America: New Madrid Fault

Jan 18, 2011
OHN 3:16 Video Ministry
51.6K subscribers

Is it due to erupt?

Video: Cascadia: The Earthquake that will Destroy Westcoast America

Jul 14, 2020
Geographics
562K subscribers

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Source/Further reading:

In-depth feature from the New Yorker: https://www.newyorker.com/magazine/20…
Detailed piece from Scientific American: https://www.scientificamerican.com/ar…
The mythology of the 1700 quake: https://blogs.scientificamerican.com/…
More on the mythology – excellent examples: https://slate.com/technology/2015/09/…
Could Cascadia trigger the San Andreas fault? https://www.nwpb.org/2019/12/03/the-b…
The science-y bit: https://earthquake.usgs.gov/data/crus…
Cascadia on a map: https://www.nwpb.org/wp-content/uploa…

Twitter is filled with South Florida residents posting about the unexplained shaking.

By CBSMiami.com Team
January 16, 2021 at 10:07 am
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The United States Geological Survey is not reporting any activity in South Florida, however, there was a strong 5.9 magnitude earthquake in Guatemala’s capital Friday morning. The U.S. Geological Service said the earthquake’s epicenter was located just off Guatemala’s Pacific coast 3 miles south-southwest of Champerico. The USGS has not linked the earthquake in Guatemala to the what people felt in South Florida.

Florida is known for having the fewest earthquakes of any US state because it’s not located near any tectonic plate boundaries, however, earthquakes do happen. They are just very rare.

In September 2020, there was a magnitude 4.0 earthquake near the Florida/Alabama state line.

But one of the most notable events in Miami took place nearly one year ago. It was Jan. 28, 2020 when buildings in Miami had to be evacuated after a magnitude 7.7 earthquake rattled off the coast of Jamaica and was felt along the east coast of South Florida.

Reports Of Unexplained Shaking Rattles South Florida Residents On Friday

By CBSMiami.com Team
January 16, 2021 at 10:07 am
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Did your house or office shake and rattle Friday afternoon?

People across South Florida are reporting they felt their homes shake, similar to a small earthquake.

The City of Weston even posted a tweet that reads, “In regard to the rumbling that people in Weston felt just earlier. There was NO explosion in #Weston. There are reports this was felt in several counties. We do not have definitive information on what caused it at this time.”

A CBS4 viewer said in an email her “sliding glass doors and windows shook violently. I’m in West Kendall. Friends as faar south as marathon and Islamorada felt it and as far north as Davie and Lauderhill.”

She was not alone.