The energy released by the earthquake on December 26, 2004 was roughly equivalent to that of the global nuclear arsenal or annual global energy consumption.
RIA Novosti asked Dr. Shebalin to give his view on the global situation.
Question: Such high global seismic activity was last recorded at the turn of the 20th century (though precise data is unavailable due to the lack of global instrumental observations at the time). Between 1965 and 2004 no earthquake similar to the Indonesian quakes was recorded. Does this mean that we are witnessing a new period of global seismic activity?
Answer: Many Russian scientists certainly think so.
Q.: Where can earthquakes occur?
A.: Major earthquakes are most likely to occur within the circum-Pacific seismic belt, which is found along the rim of the Pacific Ocean. Such earthquakes also occur within the Mediterranean belt, which extends from the Cape Verde islands across Portugal, the Mediterranean and Black seas to Asia Minor, the Himalayas and Indonesia and branches off towards Central China. Although less frequent, major earthquakes within the Mediterranean belt can be devastating given the high population density. For example, the Tangshan earthquake in 1976 and the Sumatra earthquake in 2004 killed between 50,000 and a million people.
The only comparable disaster within the circum-Pacific seismic belt was the 1923 tragedy in Tokyo, when about 150,000 died.
In Russia, seismic risk is highest in the Kuril-Kamchatka region, where earthquakes as powerful as the Sumatra 2004 quake are quite possible. For example, the earthquake that occurred to the south of Kamchatka in 1952 was one of the five most powerful quakes in the last 100 years. Other Russian regions of high seismic risk are the North Caucasus, Lake Baikal, Altai and the Sayany Mountains, but earthquakes with a magnitude of more than 6.5 are unlikely in these areas.
As regards the consequences of earthquakes, it should be noted that it is not only earthquakes with a magnitude of 8.5 and higher that can be particularly dangerous. If the epicenter of a relatively moderate earthquake is close to large cities, then the damage caused can be catastrophic. For example, although the 1976 Tangshan earthquake in China had a magnitude of only 7.6, it was the most serious disaster of the 20th century. The official death toll was 255,000 but unofficial estimates put the figure at least twice that. In comparison, the most powerful earthquake ever recorded, the magnitude 9.5 Chilean earthquake in 1960, which like the earthquake of December 26, 2004, caused a huge tsunami, but does not even make it on to the list of the thirty worst disasters.
Q.: Can earthquakes be predicted?
A.: In addition to taking measures to prepare for earthquakes, Russia is conducting research in the field of earthquake prediction. One of the leading research centers is the International Institute of Earthquake Prediction Theory and Mathematical Geophysics, of the Russian Academy of Sciences, which was founded and is still headed by Vladimir Keilis-Borok. Aided by American scientists, the Institute has managed to prove that, in principle, it is possible to predict seismic activity.
A team of scientists from the Institute and California State University in Los Angeles, led by Keilis-Borok, has developed a new method, which has substantially improved the accuracy of earthquake prediction and reduced the number of false alarms. Two earthquakes have already been accurately predicted, both about six months in advance: the earthquake off the coast of the Japanese island of Hokkaido on September 25, 2003, and the earthquake in Central California on December 22, 2003. In addition, predictions of an earthquake on the Slovenian-Austrian border in July 12, 2004 and a series of quakes in Japan in September and October 2004 turned out to be largely accurate.
It is still too early to determine how successful this prediction method will be. However, it is clear that a significant breakthrough in earthquake prediction is imminent.
Pyotr Shebalin, Doctor of Physics and Mathematics and Academic Secretary of the International Institute of Earthquake Prediction Theory and Mathematical Geophysics of the Russian Academy of Sciences.
