As a nuclear-powered icebreaker crunched through 10 feet of August ice at the North Pole, Russian sailors readied two deepwater submersibles for their two-and-a-half-mile descent. Dubbed Mir 1 and Mir 2 (mir meaning “world”), the subs were aptly named—their deployment was about to catch the world’s attention. A hole opened in the ship’s wake, and the subs were lowered. At the bottom of the Arctic Ocean, one sub took seabed samples, the ostensible purpose of the mission, while the other deposited a titanium capsule containing a Russian flag, symbolically claiming this undersea turf for its homeland.
Moscow’s 2007 stunt was mocked widely for its ostentatious flouting of diplomatic etiquette but had its intended effect: other countries were rattled. Canadian prime minister Stephen Harper scurried to the Arctic for a sovereignty tour, and the Danish science minister released preliminary findings that the North Pole was, in fact, Danish.
Russia’s action helped to kick off what has become a fierce political struggle over who owns the Arctic. Russia, Canada, Denmark (through its independent territory of Greenland), Norway and the U.S. all have some sovereignty in the far north—and they are all hoping for more. Nearly a quarter of the planet’s undiscovered oil and natural gas lie above the Arctic Circle, and recent estimates suggest most of it lurks offshore. When these riches were capped year-round by solid ice, nobody gave them much thought. But now that global warming is eliminating ice and changing coastlines, the five coastal nations are eager to start drawing lines on the seafloor.
But rights to polar resources won’t be determined by planting flags in a frontier-style land rush. Rather existing treaties will parcel out new territory based on submarine geology. That legal framework puts a whole new emphasis on mapping and exploring the ocean floor at the edge of what is technically possible, because those efforts will determine what areas a given country can exploit later. When the murk settles, the Arctic will likely hold on to only two small basins as the common heritage of humankind. The rest will be at the mercy of new ownership.
The rules for claiming seabed resources stem from the United Nations Convention on the Law of the Sea (UNCLOS). Also known as the Law of the Sea Treaty, this agreement grants countries sole rights to an area within 230 miles of their coastlines, measured typically from the low-tide mark. There is one exception: if the submerged margin of the continent juts beyond this so-called exclusive economic zone, a country may extend its claim to seabed resources accordingly.
Although roughly 15 percent of the world’s oceans overlie continental margins, these bands suffer from the logistical drawbacks of land and deep sea: inconveniently deep water and uncomfortably complex terrain. An influx of mapping grants from Arctic coastal nations has spurred an all-out assault on these data black holes, unprecedented in its scale and speed.
As the border of a continent extends underwater from the shoreline, the submerged shelf resembles coastal land beside it. This shallowly submerged extension of the land is known as the continental shelf. Deep underneath the open sea lies the other major topographic surface of the seafloor, the relatively flat abyssal plain.
Both the continental shelf and the abyssal plain have been surveyed more or less extensively. The sloping transition zone between them, however, represents a belt of ignorance. Generally, the flat shelf breaks at around 350 feet below sea level, where an abrupt drop signals the start of the continental slope, followed at two or three miles deep by a more level segment called the continental rise. It is the meeting point between the continental rise and the abyssal plain that marks the margin’s outer edge. This boundary can make or break a territorial claim over seabed resources but is often masked by thick sediment layers or other confounding features.