text: The region contains the National Petroleum Reserveâ `` Alaska , with the bulk of Alaska 's known petroleum until the Prudhoe Bay Oil Field was discovered in 1968 , as well as the Arctic National Wildlife Refuge , which itself has been the subject of controversy surrounding the possibility of petroleum drilling within its boundaries .
simplified: The National Petroleum Reserveâ `` Alaska and the Prudhoe Bay Oil Field are the two biggest areas where oil is found . The Arctic National Wildlife Refuge is there also , and there has been a lot of debate about drilling for oil there .