December 9, 2012 20:50
December 5. The study, conducted by researchers at Stanford University, focuses on the geological characteristics and activity in the Himalayas and in the Pacific Northwest.
The data obtained from surveys, geophysics will present at the American Geophysical Union meeting this week in San Francisco. Among the many presentations will be few studies that relate to the prediction of a major earthquake in the Himalayas and in the Pacific Northwest.
At 45 meeting of the Union (AGU) will meet about 20 000 scientists, teachers, students, administrators who deal with the earth and the cosmos.
Large Himalayan thrust has historically been responsible for the earthquake magnitude 8 to 9 points every few hundred years.
The Himalayan mountain range was formed, and remains active in the continuing clash of Indian and Asian continental plates. Scientists have known for some time that India dives under Asia, and have recently begun to study this complex variable impact zone in more detail, in particular, the fault that separates the two plates, the Great Himalayan thrust (MHT).
Previous observations have shown relatively homogeneous fault plane, which went down a few degrees to the north. To get a more accurate picture of the fault, Warren Caldwell, geophysics graduate student at Stanford University, conducted an analysis of seismic data from 20 seismometers deployed in over two years in the Himalayas, with the help of colleagues from the National Geophysical Research Institute of India.
Data is displayed on a small dipping thrust 3:58 degrees north, as previously expected, but was also found fault segment with a steep dip (15 degrees down) a length of 20 km. This slope gave grounds to suggest the birth of a new point of a massive earthquake in the Himalayas.
While Caldwell said his research is focused on getting pictures of events, not the prediction of earthquakes, he noted that the area has historically been responsible for the strongest earthquakes every few hundred years.
"What we are seeing is not saying that we are in a new cycle of the earthquake, but it is important to determine the future of the seismic event," — said Caldwell. "Our observation bias, located a little further north than previously observed, shows an increase in the width of the gap and the possibility of a major earthquake."
Caldwell adviser, a geophysicist, Professor Simon Klemperer, added that recently discovered magma and water around the subduction zone indicate which segments of the thrust will be torn by the earthquake.
"We believe that the gap is possible south on the surface of the Earth, but we do not expect significant breaks the surface to the north of the region," — said Klemperer.
The results are of great importance for the preparation of a risk assessment and disaster for densely populated cities in the region.