If the edge of Plate A suddenly flips upward, a large amount of water may be displaced. What could be formed at the surface of the ocean?
The correct answer and explanation is:
Correct Answer: A tsunami
When the edge of Plate A suddenly flips upward, it can displace a large volume of seawater almost instantly. This sudden movement of water at the ocean floor can generate a tsunami, which is a series of powerful sea waves caused by seismic activity beneath or near the ocean.
Tsunamis usually originate from tectonic activity, especially along subduction zones where one tectonic plate is forced beneath another. In this case, if Plate A is part of such a boundary and its edge suddenly moves upward, it shifts the water above it. This displacement sends energy outward in all directions, forming long-wavelength waves. Unlike regular ocean waves formed by wind, tsunami waves travel at very high speeds across vast distances of the ocean with little energy loss.
As these waves approach shallower coastal areas, their speed decreases, but their height increases significantly. This transformation creates large, destructive waves that can flood coastal communities with little warning. The most dangerous tsunamis result from vertical shifts in the ocean floor because they directly lift or lower large volumes of water.
The most well-known historical example is the 2004 Indian Ocean tsunami. It was caused by a massive undersea earthquake where the edge of the Indo-Australian Plate flipped upward along a subduction zone. The result was a devastating tsunami that killed over 230,000 people in multiple countries.
Tsunamis are natural hazards that highlight the close relationship between tectonic movements and oceanic behavior. Understanding how a sudden shift in a plate can affect the ocean helps in designing early warning systems and preparing vulnerable coastal populations.