Nearly one-third of the natural gas yet to be discovered in the world is north of the Arctic Circle, and most of it is in Russian territory, according to an analysis led by researchers at the U.S. Geological Survey, according to AP. «These findings suggest that in the future the ... pre-eminence of Russian strategic control of gas resources in particular is likely to be accentuated and extended,» said Donald L. Gautier, lead author of the study published in Friday's edition of the journal Science. Russia already is the world's leading natural gas producer, noted Gautier, of the Geological Survey's office in Menlo Park, California. The report, by an international scientific team, estimated that the Arctic also contains 3 percent to 4 percent of the world's oil resources remaining to be discovered. Two-thirds of the undiscovered gas is in just four areas _ South Kara Sea, North Barents Basin, South Barents Basin and the Alaska Platform _ the report said. Indeed, the South Kara Sea off Siberia contains 39 percent of the Arctic's undiscovered gas, the researchers said. Russia has been active in asserting its claim to parts of the Arctic. It first submitted a claim to the United Nations in 2001, but was rejected for lack of evidence. The United States, Canada, Denmark and Norway also have sought to assert jurisdiction over parts of the Arctic. Now, Russia is working to prove that an underwater mountain range crossing the polar region is part of its continental shelf. In 2007 two Russian civilian mini-submarines descended to the seabed to collect geological and water samples and drop a titanium canister containing the Russian flag. Arctic oil reserves are much smaller than those of natural gas and are unlikely to lead to any shift in world oil balance, Gautier said in a recorded briefing provided by Science. But they could be of importance locally if developed by individual countries, he said, citing in particular the United States and Greenland, which is governed by Denmark. However, Gautier added, the study looked only at the geological setting and the chance that energy resources are present. «If these resources were to be found they would not be found all at once. They would be found incrementally, and they would be produced incrementally,» he said, urging caution about assuming that the oil might extend world production significantly. Gautier said the study focused on geological conditions in the Arctic and how they compared to other parts of the world where oil and gas have been found. Because so much of this territory is unexplored and data is so limited the researchers had to develop a new method to do assessments, Gautier said. They collected the best information they could for the region and then subdivided it into geological areas. Those areas were compared with other geological regions around the world where gas or oil have been found in order to produce their assessment of where more resources are likely to be located. Gas and oil tend to be found in sedimentary basins, he said, and «each one of these basins has a story, a geologic story.» «As new data become available, our understanding of the resources in the Arctic will change,» he added.