Question

tsunamis are fundamentally different from normal ocean waves. explain how a subduction zone earthquake generates a tsunami and why tsunami waves cause such immense destruction when they reach the coast. * 4 points your answer

Explanation:

1. Subduction zone earthquake: One tectonic plate slides under another, causing sudden seafloor uplift or subsidence. This displaces a large volume of water, generating a tsunami wave.
2. Tsunami destruction at coasts: In deep water, tsunamis have long wavelengths but low heights. As they approach shallow coastal waters, the wave slows, wavelength decreases, and height increases dramatically (shoaling effect). This forms massive, fast-moving walls of water that flood coastal areas, destroying structures and infrastructure.

Answer:

A subduction zone earthquake generates a tsunami by causing sudden seafloor displacement (uplift/subsidence) that moves large volumes of water. Tsunamis cause immense coastal destruction because their long wavelengths compress into towering waves as they enter shallow water (shoaling), resulting in powerful, high-volume flooding.