Historic Earthquakes

Gediz, Turkey
1970 March 28 21:02:23.4 UTC
Magnitude 6.9

On March 28, 1970, a major earthquake centered
about 140 miles south of Istanbul took a heavy toll
in life and property near the Turkish town of Gediz.
A preliminary report of the earthquake,
its effects, and its geologic and historical setting follows.

1970 03 28 Turkey Earthquake

The earthquake struck a few miles east of Gediz at 2 minutes 23 seconds past the hour of 11 p.m. local time, and centered in the shallow layer less than 33 kilometers (20.5 miles) deep, with epicenter at 39.2 degrees North, 29.5 degrees East.

The shock reduced at least 33 towns of Turkey's high Anatolian Plateau to rubble, killed more than 1,000 persons, and left thousands refugees in their own land. The earthquake stopped power generators and broke telephone cables, completely disrupting communications over a wide area. Landslides covered main arteries and slowed relief to many villages.

The terror of the night was heightened by fire, caused by broken powerlines and overturned stoves and oil lamps. Flames raced through the broken shells of villages, adding to the misery of the frightened survivors. Some officials have reported that fire in Gediz killed more people than the quake itself, a situation that is reminiscent of the great San Francisco shock of April 1906.

Scattered clouds and rain showers had drifted in across the high grain and pasture lands of the Plateau. A cold front out of the European northlands angled in behind this weather, and passed through the Gediz area a few hours after the earthquake. A stationary low developing along this front brought cold, torrential rains, which checked the fires; however, this rainfall, mixed with hot ground water squeezed through cracks in the earth, raised the threat of floods. Rivers later overflowed in the area, submerging many homes built near their banks.

Relief efforts began the next day (March 29) to those towns that could be reached.

1970 03 28 Turkey Earthquake
Although checked by heavy rains, fires continue to plague stricken Gediz four days after the earthquake. Refugee tents in foreground are part of Turkish Red Crescent relief. Wide World Photo.

The U.S. Air Force Base at Cigli, Turkey, rushed trucks with water, a portable hospital, medicine, food, and communications. Food, water, and temporary shelter were vital to the prevention of epidemic and the mitigation of suffering. many countries join together to aid each other in times of disaster, and such aid was generously funneled into the Turkish Red Crescent (Red Cross).

By now, the exodus of thousands of terrified survivors had begun, using army trucks, horse carts, donkeys, or any other mode of transportation that would carry them to safety and shelter in main centers.

Rescue workers checking through the broken homes and rubble for injured and dead were hampered by continued cold rain and frequent aftershocks. Thousands of slight aftershocks were recorded, many sharp and damaging to some towns. Despite warning, some residents were driven to take shelter in homes still standing. As a result, a strong shock on March 31 killed 24 in the village of Simar and 95 in Emet; another on April 2 destroyed the 15 remaining houses in Karamanca and took one life.

1970 03 28 Turkey Earthquake
Survivors search for trapped victims of the earthquake, which took more than 1,000 lives, virtually destroyed Gediz, and flattened villages for miles around. Wide World Photo.

Gediz, Turkey, is located on the edge of the Alpide seismic zone which covers western Europe. The city's 600-year-old mosque, now a mass of rubble, testifies to the rarity of major earthquakes in the immediate area; but for Turkey as a whole, earthquakes are not so rare.

Turkey's northern section is traversed for a distance of 500 miles east to west by the great Anatolian Fault, often compared to California's San Andreas. This fault has been responsible for some 13 large, frequently disastrous, earthquakes since 1938. It is part of the Alpide seismic belt which extends from Indonesia across northern India (24 killed, 200 injured at Broach, India, March 23, 1970) across southern Russia (10 killed, Tashkent almost destroyed in 1966) to Iran (11,000 killed in Kakh area in 1968) to Yugoslavia (1,100 killed in Skopje in 1963) and on to Morocco (14,000 killed in Agadir in 1960).

The Alpide seismic zone has more than earned it reputation as a killer.

Although only about 17 percent of the world's large earthquakes occur in the Alpide seismic belt, which covers most of Turkey, a large part of earthquake fatalities throughout history has been sustained in this zone. This is due, primarily, to construction practices in the region, where rough rock and weak mortar and adobe are common building materials. These natural materials provide good protection from the heat of summer and the cold of winter; but in strong earthquakes, they virtually ensure the instant burial of their occupants.

Abridged from Earthquake Information Bulletin, May-June 1970, Volume 2, Number 3.