On the rocky beaches of Alaska, scientists plunged shovels and picks into the ground and dug 6,775 holes, repeatedly striking oil — still pungent and dangerous a dozen years after the Exxon Valdez infamously spilled its cargo.

More than an ocean away, on the Breton coast of France, scientists surveying the damage after another huge oil spill found that disturbances in the food chain persisted for more than a decade.

And on the southern gulf coast in Mexico, an American researcher peering into a mangrove swamp spotted lingering damage 30 years after that shore was struck by an enormous spill.

These far-flung shorelines hit by oil in the past offer clues to what people living along the Gulf Coast can expect now that the great oil calamity of 2010 may be nearing an end. [ NYTIMES.com ]