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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region Forums7.0 earthquake about 7 miles outside Acapulco tonight
A powerful earthquake with a preliminary magnitude of 7.0 has struck Acapulco in southern Mexico, seismologists and residents say. Details are still limited but shaking was felt as far away as Mexico City.
The earthquake, which struck at 8:47 p.m. local time on Tuesday, was centered just north of Acapulco, a city and major seaport on Mexicos Pacific coast. The area is about 240 kilometers (150 miles) south of Mexico City.
The U.S. Geological Survey (USGS) put the earthquakes preliminary magnitude at 7.0, down from an earlier estimate of 7.4. It struck about 12 kilometers below the surface, making it a very shallow earthquake.
Details about damage or casualties were not immediately available, but shaking was felt as far away as Mexico City, where power outages and gas leaks were reported.
https://bnonews.com/index.php/2021/09/powerful-earthquake-hits-southern-mexico/
2naSalit
(86,048 posts)5.0 in Greece and a smaller on in Marianas Island. Almost a straight line in Lat.
JoanofArgh
(14,971 posts)2naSalit
(86,048 posts)Shanti Shanti Shanti
(12,047 posts)NH Ethylene
(30,793 posts)I wonder if this is a typical day or if it's unusual.
Demobrat
(8,915 posts)A 7.0 took down freeways and buildings in San Francisco. Not good.
LeftInTX
(24,546 posts)Link to tweet
https://en.wikipedia.org/wiki/Earthquake_light
I hope everyone is as safe as possible. It looked like the epicenter is right there...Safety also determined by substrate.
Lucinda
(31,170 posts)KY_EnviroGuy
(14,483 posts)Earthquake and lighting storm, Mexico, September 7th 2021
Poor animals. Sounds like every dog in Mexico City was going crazy.
Thanks to LeftinTX for the Wiki link:
Quote:
Research into earthquake lights is ongoing; as such, several mechanisms have been proposed. Positive Holes is one such model.
Some models suggest the generation of earthquake lights involve the ionization of oxygen to oxygen anions by breaking of peroxy bonds in some types of rocks (dolomite, rhyolite, etc.) by the high stress before and during an earthquake. After the ionisation, the ions travel up through the cracks in the rocks. Once they reach the atmosphere these ions can ionise pockets of air, forming plasma that emits light. Lab experiments have validated that some rocks do ionise the oxygen in them when subjected to high stress levels. Research suggests that the angle of the fault is related to the likelihood of earthquake light generation, with subvertical (nearly vertical) faults in rifting environments having the most incidences of earthquake lights.
One hypothesis involves intense electric fields created piezoelectrically by tectonic movements of quartz-containing rocks such as granite.
Another possible explanation is local disruption of the Earth's magnetic field and/or ionosphere in the region of tectonic stress, resulting in the observed glow effects either from ionospheric radiative recombination at lower altitudes and greater atmospheric pressure or as aurora. However, the effect is clearly not pronounced or notably observed at all earthquake events and is yet to be directly experimentally verified.
During the American Physical Society's 2014 March meeting, research was provided that gave a possible explanation for the reason why bright lights sometimes appear during an earthquake. The research stated that when two layers of the same material rub against each other, voltage is generated. The researcher, Professor Troy Shinbrot of Rutgers University, conducted lab experiments with different types of grains to mimic the crust of the earth and emulated the occurrence of earthquakes. "When the grains split open, they measured a positive voltage spike, and when the split closed, a negative spike." The crack allows the voltage to discharge into the air which then electrifies the air and creates a bright electrical light when it does so. According to the research provided, they have produced these voltage spikes every single time with every material tested. While the reason for such an occurrence was not provided, Professor Troy Shinbrot referenced the light to a phenomenon called triboluminescence. Researchers hope that by getting to the bottom of this phenomenon, it will provide more information that will allow seismologists to better predict earthquakes.
From: https://en.wikipedia.org/wiki/Earthquake_light
KY...... .....