GEOLOGY

Detailed explanation-1: -To generate a tsunami, the fault where the earthquake occurs must be underneath or near the ocean, and cause vertical movement of the seafloor (up to several meters) over a large area (up to a hundred thousand square meters).

Detailed explanation-2: -The sudden vertical displacements over such large areas, disturb the ocean’s surface, displace water, and generate destructive tsunami waves. The waves can travel great distances from the source region, spreading destruction along their path.

Detailed explanation-3: -Earthquakes generally occur on three types of faults: normal, strike-slip, and reverse (or thrust). Tsunamis can be generated by earthquakes on all of these faults, but most tsunamis, and the largest, result from earthquakes on reverse faults.

Detailed explanation-4: -A tsunami is a series of extremely long waves caused by a large and sudden displacement of the ocean, usually the result of an earthquake below or near the ocean floor. This force creates waves that radiate outward in all directions away from their source, sometimes crossing entire ocean basins.

Detailed explanation-5: -It is this sudden vertical displacement of the ocean floor that typically sets a tsunami in motion. As the ocean floor rises or falls, so too does the water above it. As the water moves up and down, seeking to regain its balance, a tsunami is born. Not all earthquakes cause tsunamis.