These cliffs are near the top of a giant landslide. In some ways, scientists know more about the surface of the moon than about the bottom of the ocean.
Marine geophysicists add to that knowledge in several ways.
The wave reflects off boundaries between rock layers, and the reflected waves travel back up through the rocks and water to the ship. By analyzing when the waves return to the ship, Morgan can learn about the depths and compositions of layers below the ocean floor. One of the largest landslides happened about one million years ago, when one-third of Oahu's Koolau volcano suddenly slid into the ocean. Although no record exists, the landslide must have spawned a tsunami, or giant wave, that traveled all the way across the Pacific. By understanding how landslides happen, Morgan hopes to predict what kinds of tsunamis and related coastal damage the landslides will cause.