Posted on 04/18/2016 9:38:20 AM PDT by Red Badger
Rescuers and a search dog check the damage around a landslide area caused by earthquakes in Minamiaso, Kumamoto prefecture on April 17. ============================================================================================================
TOKYO -- Seismic activity in southern Japan is mystifying geologists and keeping the nation on edge.
The island of Kyushu has been struck by a series of significant earthquakes, with the epicenters moving progressively further inland. The cluster started with the deadly quakes that hit Kumamoto Prefecture last Thursday and Saturday. Temblors subsequently rocked the Mount Aso region and neighboring Oita Prefecture.
There is a known concentration of faults in the area. Still, experts say it is highly unusual to have a string of quakes measuring around magnitude 6 and stretching over such a vast area. The epicenter of the Oita jolt was about 100km away from the first Kumamoto quake.
"I don't quite understand what is happening with the recent earthquakes, because it's an unfamiliar phenomenon," said Yoshihisa Iio, a professor at Kyoto University's Research Center for Earthquake Prediction.
The Japan Meteorological Agency said it is unprecedented to have a group of large quakes in these three parts of Kyushu. Experts are divided over how far the shaking will spread and whether it could prompt more quakes centered elsewhere.
Linked faults
The Beppu-Shimabara graben -- a type of geological formation -- stretches east to west across Kyushu, through Oita and Kumamoto prefectures. A number of faults run underground. Scientists believe such concentrations of faults increase the chances of what they call earthquake swarms. When one fault shifts, causing an earthquake, it can add to the strain on other faults, triggering more tremors.
The government's earthquake research committee attributed the magnitude-6.4 quake that hit Kumamoto last Thursday evening to a shift in the northern part of the Hinagu fault zone. The magnitude-7.3 quake that struck in the wee hours of Saturday morning occurred in the Futagawa fault zone, which runs just north of the Hinagu zone, the Geospatial Information Authority of Japan said.
Part of the Futagawa fault zone, about 27km in length, slid by around 3.5 meters, according to the GSI.
The government committee met on Sunday and agreed that the Futagawa zone was the culprit in the main quake. This zone, it turns out, is longer than previously thought and stretches close to Mount Aso's caldera. The committee warned local residents to brace for more aftershocks.
Indeed, aftershocks continue in the Kumamoto, Aso and Oita regions. According to the Meteorological Agency, Kumamoto has seen the second-highest number of inland earthquakes on record, after those set off by the earthquake that hit the northwestern prefecture of Niigata in 2004.
Meanwhile, the GSI said the main Kumamoto quake unleashed 40% more seismic energy than the devastating 1995 earthquake. Saturday's quake "may have impacted nearby faults," said Hiroshi Yarai, director of the GSI's crustal deformation research division. Signs point to the quake nudging the Beppu-Haneyama fault zone in Oita, which lies northeast of the Futagawa zone.
The Beppu-Haneyama zone, in turn, is linked in the east to the Japan Median Tectonic Line -- a huge fault structure that extends through western Japan, including the island of Shikoku and the Kii Peninsula in Wakayama Prefecture. This raises the possibility that the Kumamoto earthquakes could cause a broader chain reaction across the Bungo Channel in the Shikoku region.
For now, though, a Meteorological Agency official said that "the Median Tectonic Line doesn't seem to have been activated yet."
The first thought on my mind was, Suspicious no sightings of Godzilla? Hmmmmmm.
earthquake ping
Godzilla's Mating Season?...................
Nibiru closing in!
Maybe all that Fracking woke up the big G.
/s
"Wanna meet for lunch?"
So scientists don't know everything??? But...but...global warming!
Secondly, those quakes that were shallow could be attributed to the regions volcanics, which includes the MT ASO caldera which is a hot spot that rivals Iceland's and our very own Yellowstone.
The fact that there is lineal migration to the north certainly makes me think something other than tectonic.
Magma chamber filling up...........................
Yeah certainly would be a thought.
Mount Aso volcano erupts following violent earthquake streak in Japan (VIDEO)
https://www.rt.com/news/339788-japan-volcano-eruption-quakes/
Yeah they evacuated over 200k people from the area. Though of course some of that was do to damage, a solid reason for that massive of an evac has to be the volcano risk.
The fault is behaving like any crack in a solid, after an earthquake releases the strain on one part of the fault then all of the force exerted on the two plates shifts to the next “stuck” area along the fault an that will be the next to go.
For those like me who don’t know the term “graben”:
In geology, a graben is a depressed block of land bordered by parallel faults.
....sorry michelle O has an alibi..
Meanwhile in America:
Yellowstone Eruption In 2016? Shocking New Video Shows What Is Really Going On At Yellowstone
ping.
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