body of evidence
indicates that the
triggered by the
mass loading and
by the Zipingpu
After the May 12, 2008 earthquake in Wenchuan, Sichuan,
suspicion grew among Earth scientists that the Zipingpu Dam
reservoir had triggered the devastating earthquake, which killed
more than 80,000 Chinese citizens. Since then, some 50 to 60
articles and studies have investigated this massive seismic event
and its relationship to the Zipingpu reservoir. This paper reviews
the literature and concludes that the mounting body of evidence
and analysis indicates that the magnitude 8 earthquake
triggered by the mass loading and increased pore pressure caused
by the Zipingpu reservoir. It also concludes that the initial
seismogenic rupture of the Wenchuan earthquake did not occur
along the Yingxiu Fault Belt at a depth of 14 to 19 kilometres, as
previously thought, but at a depth of 6 to 9 km along the ShuimoMiaoziping Fault Belt, which passes underneath the Zipingpu
reservoir. This initial seismogenic rupture subsequently expanded
and spread in a series of rupture events that were closely linked to
each other for 90 seconds along the Longmenshan Central Fault,
moving 200-300 km from southwest to northeast. The near absence
of a typical precursor
before the Wenchuan earthquake, in
addition to seismic recordings of abnormal, small earthquakes in
the reservoir area as early as April 5, 2008, suggest that this was
not a conventional case of reservoir-induced seismicity (RIS) in
which the accumulation of stress in a fault zone is nearing the
critical point, and the impounding activities of a reservoir merely
trigger the inevitable seismic event. Rather, the new findings
suggest that the filling and drawdown of the Zipingpu reservoir
triggered clusters of small earthquakes which caused new ruptures
in the rock that, in turn, altered the stress field in the Longmenshan
region and led to an accelerating release of energy. This series of
events culminated in the giant rupture that became the MS8.0
Wenchuan earthquake. In light of these findings, Earth scientists
and decision-makers alike must now address a dangerous new
reality: if reservoir-induced seismicity can be considered humaninduced foreshocks to a major earthquake, then the science of
reservoir-induced seismicity must consider the possibility that reservoirs can trigger unanticipated tectonic activity. Most
urgently, the findings presented in this paper about the Wenchuan
earthquake make a review of current plans to build dozens of large
dams with accompanying large reservoirs, in and near areas of
high regional tectonic stress in western China, a high priority.
Google issued a Public Alert on the Earthquake measuring 7.3 Richter 1 hour, 19 minutes agoLocation: 176 miles (284 km) E of Sendai, Honshu, Japan; 184 miles (296 km) ENE of Iwaki, Honshu, Japan; 198 miles (319 km) E of Fukushima, Honshu, Japan; 285 miles (459 km) NE of TOKYO, Japan. Source: U.S. Geological Survey.
The wave was recorded in Ishinomaki, a city in Miyagi prefecture that was badly hit by the tsunami of March 2011, which killed thousands.
Earlier, a strong earthquake struck off the coast of northeastern Japan in the same region that was hit by a massive earthquake and tsunami in March 2011.
The Japan Meteorological Agency said the earthquake had a preliminary magnitude of 7.3 and struck in the Pacific Ocean off the coast of Miyagi prefecture.
The epicentre was 10km beneath the seabed.
Initial warnings said the tsunami could be as high as 2m.
There is no tsunami warning current for Australia or neighbouring nations.
NHK television broke off regular programming to warn that a strong quake was due to hit shortly before the earthquake struck. Afterward, the announcer repeatedly urged all near the coast to flee to higher ground.
It caused severe damages and at least 15 people were killed.
“More than 50 aftershocks struck northern Italy overnight as thousands of people slept in tents or out in the open for fear of returning to their homes, a day after 16 people lost their lives and more than 300 were injured by a powerful earthquake.
The aftershocks rattled the nerves of the 14,000 people who have been left homeless by the earthquake which hit Emilia-Romagna on Tuesday and a previous one which hit the region on May 20.
Rescuers were searching for one missing person – the employee of an electronics warehouse in the town of Medolla, one of the towns at the epicentre of the quake.
Experts said the aftershocks could continue for days or even weeks, compounding the fear and uncertainty of the tens of thousands of people affected by the natural disaster in a triangle between the cities of Bologna, Ferrara and Modena.
“The aftershocks could go on for several weeks, or even months,” Andrea Morelli, the director of the National Institute of Geophysics and Vulcanology, told Corriere della Sera newspaper.
The president of the institute, Stefano Gresta, said: “One cannot exclude the possibility that there could be more powerful earthquakes.” Tuesday’s earthquake hit towns and villages which were already battered from the quake of May 20.
How insensitive can one get in the pursuit of money!
While millions of people evacuated the coastline along the Indian Ocean following the 8.6 magnitude earthquake that shook northern Indonesia Wednesday, KFCThailand insisted that they rush home and order a bucket of chicken.
Local authorities along the Indian Ocean rim braced for a disastrous tsunami, people fled for higher ground. According to the Associated Press, in an inopportune moment KFC posted on its Facebook page: “Let’s hurry home and follow the earthquake news. And don’t forget to order your favorite KFC menu.”
By the time tsunami warnings subsided, hundreds of people began lambasting the company on Thai web pages, prompting the immediate removal of the message. An apology replaced the post, asking for forgiveness for the error.
For many, Wednesday’s earthquakes served as a painful reminder of the devastating outcome of the Asian tsunami in 2004 that claimed 230,000 lives in the same region.