Tsunami maps for California's central coast show an unusual risk
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While no one but scientists using remotely operated vehicles can see the canyon, geologists are on the watch for its effects — most notably, the underwater landslides and avalanche-like movement of sediment that carve out its deep trenches. Recent improvements to underwater mapping and exploration have helped them discover more about the processes that shaped the canyon, and they know that one landslide, if large enough, could in theory cause a major tsunami in the surrounding area.
While the risk is extremely small — there’s no evidence that an underwater landslide in the canyon has caused a devastating tsunami in thousands of years — geologists have incorporated the risk into tsunami hazard zone maps for Santa Cruz and Monterey counties just in case. And they continue to study the canyon to learn more about the forces that shaped it.
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Though the chance of a major tsunami generated by a large landslide within Monterey Canyon itself is tiny, the California Geological Survey incorporated the risk in its tsunami hazard maps for Santa Cruz and Monterey just in case.
“It’s really one of these events that is very, very unlikely to occur. We don’t expect to have that particular event occur in the near future,” said Rick Wilson, senior engineering geologist at California Geological Survey, which publishes the maps. At the same time, he said, “We really want to sell that point that tsunamis are tricky so that people are aware they’re not always going to get a warning.”
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