DISTRIBUTION OF EARTHQUAKES

The distribution of earthquakes is more or less similarly to that of volcanoes. The earthquakes mostly occur in weak crustal areas of the earth.

Cir cum-Pacific Belt. About 68% of world’s earthquakes are observed along the coasts of vast Pacific Ocean. This is known as the ‘ring of fire’. This is the area of intense volcanic activity also. This areas is closely linked with the region of crustal dislocations and volcanic phenomenon. Chile, California, Alaska, Japan, Philippines, New Zealand and the mid-ocean areas have had many minor and major earthquakes in this belt. Mountains here run along the border of continents and nearly parallel to the depressions in oceans. It causes sharpest break in relief which becomes a cause for the earthquakes.

Mid-world Mountain Belt. Nearly 21% of world’s earthquakes occur in the mid-world mountain belt. It extends parallel to the equator from Mexico across. Atlantic oceans, the Mediterranean Sea, from Alpin-ecaucasus ranges to the Caspian, Himalayan Mountains and the adjoining lands. This zones has folded Mountains, large depressions and active volcanoes.

Minor Belts. This remaining 11% of the shocks are recorded outside these two belts. Only a few occur along the fracture in Africa lakes, Red and Dead Sea zone.