Tsunami may strike again anytime
Scientists who conducted the seismic autopsy of the killer-tsunami that devastated Indonesia, Thailand and other Asian countries warned that earthquakes bringing killer tsunamis may strike again.
According to the news, the scientists draw the conclusion that conservative seismic forecasts may not serve society well based on the following
observations: The earthquake
2. it made the entire Earth “ring like a bell” as its seismic signals caused the planet’s crust to vibrate in oscillations picked up by seismographs worldwide — from instruments emplaced in the steppes of Russia to others buried beneath the Antarctic ice sheet.
3. It released the energy of 100 billion tons of TNT — more than the power of a thousand 1-megaton hydrogen bombs.
4. The waves of the tsunami it created were so high as they crossed the Indian Ocean that satellites orbiting overhead had no trouble identifying them through radar measurements of the wave troughs.
5. The Sumatra quake involved a complex set of abrupt movements among the miles-thick slabs of the Earth’s crust that make up the constantly shifting tectonic plates of the East Indian region — where earthquakes have threatened human populations for centuries.
According to a team from UC Berkeley, the U.S. Geological Survey in Menlo Park and the Institute of Himalayan Geology in India, the quake began just off Banda Aceh in Northern Sumatra when the ocean floor of the India plate suddenly plunged northeastward, diving as much as 60 feet underneath the Burma sub-plate. That process, called subduction, released centuries of strain that had built up along the unnamed fault.
At the same time, the lip of the Burma sub-plate surged upward, creating an enormous mass of ocean water — at least seven cubic miles in volume — that became the murderous tsunami, spreading death throughout the vast region as it sped across the Indian Ocean to the coast of East Africa.
