9d7b1f36-d5ce-4818-9aa1-81ac5cc2c17d urn:uuid eng UTF-8 nonGeographicDataset nonGeographicDataset 2025-10-16T22:24:56 creation ISO 19115 2016 Tsunami Animation - Subduction Inundation Crest 9d7b1f36-d5ce-4818-9aa1-81ac5cc2c17d Depending on whether the first part of a tsunami to reach the shore is a crest or a trough, it may appear as a rapidly rising or falling tide, and in some cases the tsunami may appear as a series of breaking waves. People near the beach may also hear a roaring sound, like an approaching train. In this example, the first crest of our tsunami arrives without warning and inundates the beach and low lying land causing extensive damage. After the first wave, the water will draw back and then the second and third waves will repeat the process at 15 to 20 minute intervals. The first wave may not be the biggest. Reefs and offshore islands may help to protect the coast from the devastating effect of a tsunami. Earth Sciences Multimedia Published_External tsunamis Download the movie documentDigital Download the movie video/x-flv Unnamed resource documentDigital HTML