10/22/2014 — “Global Surge” in Earthquakes admitted and discussed at Geological Society Meeting

Larger earthquakes, and multiple volcanic eruptions are the sign of it.  Tsunamis, injuries, damaged infrastructure, and human casualties are the result of it.

What is “it”?

“It” is Global seismic activity.  And “it” is picking up in pace.

Watch the video report here:


Researchers online have been calling it a “global unrest event” for the past 3 years or so… on the other hand, most “professionals”, and professional skeptics have been in denial, saying “everything is normal”, and that “earthquakes happen all the time”.

The average person on the street is most likely completely unaware that anything out of the ordinary is afoot, geologically / volcanically speaking that is to say. The amount of resistance I’ve personally been met with, when putting out earthquake + volcano posts saying there is an “uptick” or “global unrest” underway, has been phenomenal.

Now, we come to find out that the “professionals” are discussing what THEY are calling a “global surge” of earthquakes — the surge apparently began in 2004, and carries on to today.

Recent examples of the 8.0M+ earthquake “surge”:

8.0m alaskaa

Above: June 23, 2014 – 8.0M earthquake strikes Alaska

8.7 magnitude sumatra april 11 2012

Above: April 12, 2014 – 8.3M earthquake strikes Papua New Guinea

8.0m earthquake chile april 1 2014

Above: April 1, 2014 – 8.0M earthquake strikes Chile

8-0-santa-cruz

Above: February 2, 2013 – 8.0M earthquake strikes Santa Cruz islands

earthquakes-8-3-russia-may-23-2013

Above: May 23, 2013 – 8.3M earthquake strikes Sea of Oktusk Russia

7-7m-earthquake

Above: October 27, 2012 – 7.7M earthquake strikes British Columbia Canada

two megaquakes indonesia april 11 2012

Above: April 11, 2012 – TWO 8.0M+ earthquakes in Sumatra Indonesia along the Indo-Australia Ridge


Full article below:

http://phys.org/news/2014-10-global-surge-great-earthquakes-.html

A global surge of great earthquakes from 2004-2014 and implications for Cascadia

21 October 2014

“The last ten years have been a remarkable time for great  earthquakes.  Since December 2004 there have been no less than 18 quakes of Mw8.0 orgreater – a rate of more than twice that seen from 1900 to mid-2004.

Hundreds of thousands of lives have been lost and massive damage has resulted from these great earthquakes. But as devastating
as such events can be, these recent great quakes have come with a silver lining: They coincide with unprecedented advances in technological and scientific capacity for learning from them.

“We previously had very limited information about how ruptures grow into great earthquakes and interact with regions around them,” said seismologist Thorne Lay of the University of California at Santa Cruz. “So we are using the recorded data for these recent events to guide our understanding of future earthquakes. We’ve gained a new level of appreciation for how one earthquake can influence events in other zones.”

High on the list of areas ripe for a great quake is Cascadia, the Pacific Northwest, where the risk for great quakes had long been under appreciated. Evidence began surfacing about 20 years ago that
there had been a great quake in the region in the year 1700. Since then the view of the great quake risk in Cascadia has shifted dramatically.

“We don’t know many details about what happened in 1700,” said Lay. There were no instruments back then to observe and record it. And so the best way to try and understand the danger and what could happen in Cascadia is to study the recent events
elsewhere.

Over the last decade Lay and his colleagues have been able to gather fine details about these giant earthquakes using data from an expanded global networks of seismometers, GPS stations, tsunami
gauges, and new satellite imaging capabilities such as GRACE, InSAR, and LandSAT interferometry.

Among the broader conclusions they have come to is that great quakes are very complicated and idiosyncratic. Lay will be presenting some of those idiosyncrasies at the meeting of the Geological Society of America in Vancouver on Oct. 21.

“What we’ve seen is that we can have multiple faults activated,” said Lay. “We’ve seen it off Sumatra and off Japan. Once earthquakes get
going they can activate faulting in areas that were thought not physically feasible.”
The great Sumatra-Andaman earthquake of Dec. 26, 2004, for instance, unzipped a 1,300 kilometer long segment of the subduction zone and unleashed one of history’s most destructive, deadly tsunamis.

Much of the rupture was along a region with very limited plate convergence. In Japan, the Kuril Islands, and the Solomon Islands, great megathrust ruptures have ruptured portions of the subduction zones that were thought too warm or weak to experience earthquakes.
“These earthquakes ruptured right through areas that had been considered to have low risk,” said Lay. “We thought that would not happen. But it did, so we have to adjust our understanding.”

Perhaps the best recent analogy to Cascadia is offthe coast of Iquique, Chile, said Lay. There had been a great quake in 1877, and a conspicuous gap in quakes ever since. Like the 1700 Cascadia earthquake, there is little data for the 1877 event, which killed more than 2,500 people.

In both subduction zones, the converging plates are thought to be accumulating strain which could be released in a very large and violent rupture. On April 1 of this year, some of that strain was released offshore of Iquique. There was a Mw8.1 rupture in the northern portion of the seismic gap. But it involved slip over less than 20 percent of the region that seismologists believe to have accumulated strain since 1877.

“We have no idea why only a portion of the 1877 zone ruptured,” said Lay. “But clearly, 80 percent of that zone is still unruptured. We don’t have a good basis for assessment of how the rest will fail. It’s the same for Cascadia. We don’t know if it always goes all at once or sometimes in sequences of smaller events, with alternating pattern. It is prudent to prepare for the worst case of failure of the entire region in a single event, but it may not happen that way every time.”

What is certain is that studying these recent big earthquakes has given geophysicists the best information ever about how they work and point to new ways to begin understanding what could be in Cascadia’s future.

More information: A GLOBAL SURGE OF
GREAT EARTHQUAKES FROM 2004-2014 AND
IMPLICATIONS FOR CASCADIA

Abstract: https://gsa.confex.com/gsa/2014AM/webprogram/Paper242140.html

Session No. 178. P4. Great Earthquakes, the
Cascadia Subduction Zone, and Society I


Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s