Paw Talk - Pet Forums banner
1 - 1 of 1 Posts

·
Registered
Joined
·
0 Posts
Discussion Starter · #1 ·
after the the since the 1970s, seismologists pay close attention to the direction of the East China Sea fault southwest of Tokyo. There have not occurred since 1854 a major earthquake here 8 earthquake cycle seems to be about 150 years. within a week after the most thorough research
the same time, the other covering the whole country, To the Sendai earthquake, Hi network in the country has dense layout of the over 800 high sensitivity of the vibrometer, the average distance between the instrument in the 20-30 km.
the NOAA released the Japanese earthquake and tsunami map. Is the most concentrated area of ​​seismic energy in the vicinity of the earthquake source region and the southeastern waters, the tsunami wave height is at least more than 2.5 meters, however,nike soccer shoes, the tsunami across the Pacific Ocean to the speed of jet aircraft in the open waters of the wave height over 20 centimeters. Opinion, March 11, 2011 in the United Kingdom University of Ulster geophysicist John Mellow Chomsky, John McCloskey, the devastating earthquake in Japan is not entirely unexpected,adidas soccer shoes, because once on March 9 7.2 9.0 of the earthquake, the aftershocks of the former.
the in the circum-Pacific seismic belt is not surprising that a major earthquake, seismologists still feel a bit strange, but for the 9.0 Earthquake occurred off at Sendai. Most people will focus on the south, that is, the Tokyo Bay. The earthquake of the 21st century is to ask more questions of seismology.
United States Geological Survey (USGS), seismologists said, an earthquake of this size requires a long, straight fault rupture length of at least 300 miles. Geologists already know the existence of such faults in Peru and South America East Coast. The place where the Japanese earthquake did not exist long, straight fault, the opposite direction of the fault is very rules.
but on the other hand, use the existing knowledge of seismology to analyze this large earthquake occurrence indeed where it is difficult to understand.
According to Nature magazine reported, the 2004 Sumatra earthquake caused a doubt on the hypothesis of the oceanic crust age. Because from the age of the crust, can not occur as the scale of the earthquake. The whole of modern seismology is a hundred years of history, the better the history of modern observations of about 50 years. The earthquake has occurred in the 21st century is to the seismologist to ask more questions. The recent measurements of March 20,soccer shoes 2012, 2011, the Japanese before landing Takada, the ruins of the doll. Unexpected locations
seismologists fear, Sendai near such a big earthquake occurs, the rest of the world similar to the old oceanic crust area is also possible.
This is why the United States Geological Survey Earthquake Science Center at William (Wiliam Elsworth), Elvas believe that a major earthquake in Japan will be one of the earthquake has ever been studied most thoroughly.
subduction zone earthquake caused by the subducted oceanic plates. The oceanic plates are generally heavier, and the collision of continental plates, the oceanic plate to below the continental plate subduction. This type of earthquake can be achieved, for example, Chile 9.5 earthquake in history in 1960 and 9.1 2004 Sumatra earthquake, fall into this category.
2010 earthquake in Chile, a group of seismologists in earthquake in the region of 150 seismic stations and 30 GPS stations monitoring after a major earthquake fault activity. They found that in the past year, the fault dislocation of two to three meters. The researchers now hope that this study can figure out these slow motion exactly how to promote as a major earthquake in Chile and Japan.
this powerful aftershocks to the Earth's rotation axis 25 cm of displacement, one of Antarctica's glaciers sliding half a meter. It is the fourth major earthquake on Earth since 1900.
Sendai earthquake, Japan earthquake more than three times seven and 48 times more than 6 earthquake. Kuroi Satoko of Japan University of Tokyo Earthquake Research Institute, believes that there is evidence that the two earthquakes occurred in the west of Tokyo on March 12 and 15 is triggered by the Sendai earthquake.
earthquake occurred in the circum-Pacific seismic belt known as the The strange thing is, almost no earthquake experts believe that the plot area near Sendai,cheap soccer shoes, Japan, to produce even if it is close to 9.0 earthquake. They had always thought that 7.5 is possible. 9.0 earthquake a difference of one hundred times the energy released in 7.5.
No one knows if it is safe now Tokyo. Southwest of Tokyo, is the border of the Philippine and Eurasian plates, has been considered with a high earthquake risk. But now it seems, Sendai earthquake triggered aftershocks occurred mainly in the Pacific plate boundary.
does show the Sendai region due to plate motion occurs extrusion from the deformation of the Pacific plate stuck in there,f50 soccer shoes, but not smoothly slide in Japan below. This squeeze caused by stress release only by the earthquake. Stress accumulation is very fast, a series of small earthquakes in the past can not release it, so the March 11 earthquake. Geophysicist Thomas Sidon (Thomas Heaton,) of the California Institute of Technology, this 9.0 earthquake, are not necessarily release all the stress, mystery.
only a few scientists have warned Sendai near the possibility of a major earthquake and tsunami. In 2001, Earth scientists of Tohoku University, Japan Kei Pu Hao and colleagues in a paper pointed out that a huge tsunami in the Sendai region in AD 869. Earlier in the geologic record, the Sendai area of ​​tsunami occur once every 800-1100 years. Therefore, they wrote in their paper,
Japan earthquake, more than four hundred kilometers of fracture spent about three and a half minutes; when the fracture is still in progress, the Japan Meteorological Agency has been the help of the Hi network reported the earthquake. Reported a magnitude 7.9, but later found that earthquakes far better than this. 48 hours after the earthquake, Japan about 1200 measurement data of the GPS sites moved four meters of the crust of the central part of Honshu with the fracture occurred east.
the Some analysts believe that this may mean earthquake in the place where the existence of a previously unknown branch faults. This type of fault will be steeper the angle of the fracture, making it easier to let the seabed ground substantially perpendicular to the dislocation, triggering a huge tsunami. However, some preliminary calculations seems to exclude this possibility. Found that the fracture angle of 14 degrees, and did not show the characteristics of branch faults. The exact situation still requires more computation.
In addition, the geologists opinion, the occurrence of the earthquake and to the age of the earth's crust. Subduction zone subduction of young oceanic crust to the mantle, may cause a huge earthquake. Old crust subduction process is relatively stable, and will only lead to a series of small earthquakes. The question now is, the oceanic crust of the northeastern Japan has 140 million-year history, has been considered quite old.
Japanese seismologists actually research attention on the near Tokyo. But it is also located in the subduction zone, so the problem is that for earthquake researchers, that place is not an earthquake? That place how, why it would be more quiet? These seismologists are concerned about is the past many years.
from seismology, Sendai near the earthquake, or anywhere along the subduction zone earthquake is not surprising. Because here is indeed a very weak plate boundary between the movement of each year to reach about 8 cm, is very fast. Tokyo
the Great Hanshin Earthquake, the Japanese launched a project to upgrade the seismic monitoring network in the country. Science and Disaster Prevention Research Institute within one year to complete the distribution of the 1000 stations in the country K Kyoshin, in Japanese means K-net stations are installed above the ground.
the January, 1995 in Japan in the Great Hanshin Earthquake. At that time, Japan's seismic monitoring network has several sets of runs at the same time. Among them, the Japan Meteorological Agency in the country layout of the 188 stations, Japan Science and Disaster Prevention (NIED), Institute of Kanto, central Japan - East China Sea areas, the construction of 89 high-sensitivity stations. In addition, Japanese universities are also certain areas equipped with seismic monitoring instruments for research purposes. These monitoring network that there may be data exchange, but generally speaking, independent.
The earthquake in Japan is very reminiscent of the over last year's 8.8 earthquake in Chile. Xiaodong said,
in the process of subduction of oceanic plates, the continental plate will be deformed, which is why generally speaking subduction zone followed by island arc. The whole of Japan is to dive behind the island arc, another example, the entire South American Andes, the island arc formed by the subduction zone. Why do not earthquakes.bkwjz16.
 
1 - 1 of 1 Posts
Top