The Ocean Guardian semi-submersible drilling rig floats tethered to the sea floor just three days after beginning its second exploration well a little more than 100 km (62 miles) offshore from the Falkland Islands, April 19, 2010. The rig is being shared by different oil companies with concessions in the Falkland Basin, having drilled the first well for Desire Petroleum before beginning the current one for Rockhopper Exploration. Argentina asked the United Nations to step into its dispute with Britain over the Islands when the exploration operation was originally announced. REUTERS/Gary Clement (FALKLAND ISLANDS - Tags: ENERGY POLITICS ENVIRONMENT BUSINESS)