US extended continental shelf

US maritime limits and boundaries

The Biden administration has vastly extended US claims to sovereignty over the ocean floor by an area twice the size of California, securing rights to potentially resource-rich seabeds at a time when Washington is ramping up efforts to safeguard supplies of minerals key to future technologies.

The so-called Extended Continental Shelf covers about 386,100 square miles (1 million square km), predominantly in the Arctic and Bering Sea, an area of increasing strategic importance where Canada and Russia also have claims. The US has also declared the shelf’s boundaries in the Atlantic, Pacific and Gulf of Mexico.