Tsunami

A tsunami is a series of large ocean waves caused by the displacement of a massive volume of water, usually due to undersea earthquakes, volcanic eruptions, or landslides. An undersea earthquake displaces the seafloor, pushing the overlying water upward and creating a powerful wave. As the wave travels through the ocean, its energy is conserved, and it can travel vast distances with little loss of power. When the tsunami approaches shallower coastal areas, the wave energy is compressed, causing the wave to grow in height and inundate the shoreline with devastating force. The most common tsunamis occur along subduction zones where tectonic plates converge.

The 2004 Indian Ocean 9.1 magnitude undersea earthquake resulted from the sudden release of built-up stress along a fault line known as the Sunda Trench, located off the west coast of northern Sumatra, Indonesia. The heavier Indian Oceanic Plate, which is moving northward, is subducting beneath the Burma continental Plate along the Sunda Trench. The subduction process causes the leading edge of the Indian Plate to become stuck, accumulating stress over time. When the stress becomes too great, it is suddenly released as an earthquake, causing the seafloor to uplift and displacing a massive volume of water, triggering the tsunami and impacting the coastlines of 14 countries. The tsunamis reached heights of up to 100 feet (30 meters) and traveled hundreds of miles across the ocean at high speeds, striking coastal areas with little warning.

The 2011 Japan 9.0 magnitude earthquake was caused by the movement of the Pacific Plate beneath the North American Plate along the Japan Trench. This subduction zone is part of the Pacific Ring of Fire, known for its frequent seismic activity and volcanic eruptions. The earthquake occurred when the Pacific Plate suddenly slipped and uplifted the seafloor, generating a massive undersea displacement. The sudden upward movement of the seafloor displaced a vast amount of water, creating a series of powerful tsunami waves that propagated across the Pacific Ocean and struck the northeastern coast of Japan. The waves reached up to 133 feet (40 meters) and traveled inland for several kilometers, devastating coastal communities and causing a nuclear accident at the Fukushima Daiichi Nuclear Power Plant.

Both tsunamis caused widespread destruction and loss of life. The 2004 Indian Ocean tsunami resulted in over 230,000 deaths and affected millions across multiple countries. The 2011 Japan tsunami claimed nearly 16,000 lives and caused extensive damage to infrastructure and property.