"It's not one that's going to cause mass devastation. But it will cause coastal flooding and it will cause damage and it does put lives at risk if people don't move to high ground," an oceanography professor says.

(Reuters) -A very powerful magnitude 8.8 earthquake off Russia's Far Eastern Kamchatka coast on Wednesday triggered tsunami warnings as far away as French Polynesia and Chile, and was followed by an eruption of the most active volcano on the peninsula.