Tag: Zipingpu

The earthquake which claimed  a lot of lives besides causing extensive damages to property is now proved to be man-made and not an At of Nature.

 

A new study (PDF) published by Probe International, based on around 60 other studies of the 2008 Sichuan earthquake, backs earlier arguments that the disaster was caused by the weight of the Zipingpu dam reservoir. The authors suggest that extensive plans for further hydropower projects in vulnerable regions should be urgently reconsidered.

 

 

Is India aware of the dangers of Hydro Electric projects?

 

Report of the Study:

 

“The mounting
body of evidence
and analysis
indicates that the
magnitude 8
earthquake was
triggered by the
mass loading and
increased pore
pressure caused
by the Zipingpu
reservoir.”

 

 

 

 

“ABSTRACT
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
1
was
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
2
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
3
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.

 

http://probeinternational.org/library/wp-content/uploads/2012/12/Fan-Xiao12-12.pdf