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Two visiting geologists from the U.S. Geological Survey disclosed that a 1956 geologic map indicated that an ancient tsunami could have probably struck Saipan.

Geologists Bill Burton and David Weary, in an interview with the Saipan Tribune, pointed to the geological map showing the presence at a certain portion of the island of what they called “storm surge deposits.”

Burton and Weary explained that the idea was that large waves crashed over an area on the island and left typically broken pieces of coral reefs.

“The reason why we’re interested in this is because this may recording ancient tsunamis. So the question is are those records of ancient tsunamis just like what happened in the Indian Ocean?” Burton said.

Burton, however, stressed that the tsunami probably happened thousands of years ago.

“So you would expect over thousands of years to get one or more tsunamis,” Burton added.

He underscored the need to look at the old records to understand tsunami’s past as what had USGS volcano hazards program coordinator Dr. James E. Quick had earlier explained about ancient volcano deposits.

Quick had stated that a volcano is known as prone to explosive eruption by looking at its past records or volcano deposits.

“Looking at ancient tsunami deposits can help us figure out how frequent they are [occur]. Maybe it’s only once every 200 years or something,” Burton said.

“But just knowing that they happened in the past that sometimes suggest they may happen again in the future at sometime… we don’t know,” he said.

Burton said if one looks at the location of these deposits, then one can surmise that the areas near the coast were devastated whereas the areas on higher grounds were probably safe.

“Just like in the last big tsunami. People on the beach, in shallow water were swept away. People on the inland a little bit, were not,” he said.

Quick had also stated that preliminary results of their numerical analysis indicated that large tsunamis are unlikely to happen in the Marianas region.

Quick noted that Marianas Trench is unlikely to have large accumulation of sediments.

“It is this large accumulation of sediments that can produce submarine landslides, displaced a large amount of water in the event of an earthquake and generate large tsunamis,” he pointed out.