Death Without Warning

With the power of a one-megaton bomb, an earthquake shocked eastern Turkey last week, killing more than 100 people and injuring about 200. The quake centered in sparsely settled Tunceli and Erzincan provinces, 80 miles west of the Varto area, scene of a violent quake that killed 2,477 people last August. It was the second earthquake to sunder Turkey within five days; on July 22 about 100 people were killed and 300 injured in a series of shocks that struck 50 towns near Adapazari. Like previous Turkish quakes (see map), the latest disasters were located along the Anatolian Fault, a particularly lethal segment of the earthquake belts that coil around the globe. Along the Anatolian Fault, some 40,000 persons have lost their lives in eleven earthquakes since 1938.

Last week's catastrophe came without warning. The outside world's first indications were jiggles recorded on Russian seismographs after the destruction had started. Could the quake have been forecast?

Some scientists believe that small foreshocks may signal an earthquake days or even months before it occurs. Others are certain that changes in surface features and sea level are visible to the naked eye hours before some earthquakes. But none of this adds up to a workable warning system: earthquakes are caused by conditions so deep within the earth that they cannot be studied with present tools and knowledge.

Long-range studies of earth disturbances are planned in the U.S., Japan and Russia. Geophysicists will place ultrasensitive instruments deep in the earth. In such studies, tiltmeters will measure shifts in the position of vast subsurface areas, and, ideally, laser devices will be able to measure micro scopic expansion and contraction of bedrock, while strain seismographs monitor the kind of subsurface stress and crust slippage that occurs in fault zones.

Although such studies are highly expensive and painfully slow, scientists hope that a gradual buildup of information about the earth's crust and interior will someday enable them to create a computerized earthquake-warning system. But that day is far off. For now, says Dr. Clarence R. Allen, former director of Caltech's seismological laboratory, "these phenomena cannot be predicted--and there is no assurance that they ever will be."

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