U.S. Blocks Use of Mapping System in China By WAYNE ARNOLD he Australian mining company BHP Billiton said Friday that the United States Defense Department was blocking it from using an advanced mapping technology to search for mineral deposits in China. BHP Billiton has a license to use the so-called Falcon system, which was originally intended for use on United States nuclear submarines. BHP Billiton has been using the system around the world since 1999 to help find underground deposits of minerals from aluminum to zinc. But in a meeting this week with analysts in Australia, the head of BHP...