Posted on 09/28/2012 9:05:18 AM PDT by BenLurkin
A new study suggests that two recent earthquakes may indicate a literal seismic shift in our understanding of tectonic plate movements.
Massive earthquakes under the Indian Ocean that took place last spring are the largest of their kind ever recorded. The 8.7 magnitude quake, followed by a 8.2 magnitude aftershock, could signal the formation of a new plate boundary under the Earth.
While not the largest earthquakes ever recorded, the two quakes are notable for their unusual location. The majority of earthquakes are known as thrust faults: massive sheets of rock sliding over or under another block along a fault line. The two earthquakes recorded in April were strike-slip faults, where one block of rock slides alongside another. The April quakes, which took place off the coast of Indonesia, are the largest slip-strike faults ever observed.
Additionally, the two earthquakes took place within a plate, rather than on its edge. According to a study published in the journal Nature, the quakes were part of the breakup of the Indian and Australian subplates under the Indian Ocean. The study also increased the magnitude of the initial earthquake to 8.7 - a significant increase in power as the Richter scale which is used to gauge the magnitude of earthquakes increases logarithmically rather than linearly.
Researchers believe the earthquakes were the result of the Indo-Australian plate rending itself apart. Seismologists have suspected the plate might be breaking apart since the 1980's. But the April earthquakes are the clearest evidence yet of this phenomenon. As one scientist wrote, "The long-term scenario is that a nascent plate tectonic boundary is forming: the Australian plate is becoming detached from the Indian plate."
This detachment will take several million years to complete, but research suggests more earthquakes like the ones in April will become increasingly likely in the future.
Calm down, for God's sake. What are you getting so worked up for?
I’m always a bit amused by those who appeal to statistical error, claiming the reduced numbers of >7.0 earthquakes in prior decades/centuries were due partly to the recent numerical increase in seismometers.
It is academia at its most ignorant failure to identify their statistics with the things being measured.
If we accepted that logic, then people in remote regions just didn’t have the resources to perceive >7.0 earthquakes, or perhaps forgot about them. Such an absurd notion disproves their assertions prima facie.
Perhaps in very remote regions where nobody ventured within a 1000 miles or traversed the vicinity, and neither were there geologists to have looked at geologic records, some might have been missed,...but even then that is based upon conjecture as well.
Just looking for some honest debate given the best information at our disposal. The Centennial Catalog, particularly two charts included therin, is the best data I could find to base a discussion on and you STILL haven't commented on it. It's frustrating but it may just be my fault. My patience wears thin at times and I apologize for any sourness in my disposition.
From a layman's point of view much of "science" appears to be nothing more than conjecture. In this particular instance I'll accept the notion that the USGS' recorded and assimilated historical earthquake data is more or less accurate. I can't imagine there would be an agenda at work to prompt them to skew the data. AND, the data shows ups and downs in earthquake magnitude and frequency as far back as they have been able to measure but otherwise remarkably consistent on average.
I also found the following which similarly supports what you said:
"We continue to be asked by many people throughout the world if earthquakes are on the increase. Although it may seem that we are having more earthquakes, earthquakes of magnitude 7.0 or greater have remained fairly constant."
http://earthquake.usgs.gov/learn/topics/increase_in_earthquakes.php
In any case, I was really (initially) referring to what seems to me to be an increase in large quake activity in and around the Indonesia area over the past few decades. I kind of mixed up the two two things with that chart on activity worldwide.
Peace, FRiend.
The great Lisbon earthquake hundreds of years ago, the New Madrid quakes of 1811 to 12, a huge quake in Assam in the 1950s if I remember correctly. I guess the “later days” are turning into the later centuries.
Of course there will be disturbances, and it will take a long time. “Breaking up is hard to do...”
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