BP's upstream activities in the Lower 48 states are conducted through Denver-based BPX Energy.[1] It has a 7.5 billion barrels (1.19 billion cubic metres) resource base on 5.7 million acres (23,000 km2).[183] It has shale positions in the Woodford, Oklahoma, Haynesville, Texas, and Eagle Ford, Texas shales.[184][185] It has unconventional gas (shale gas or tight gas) stakes also in Colorado, New Mexico and Wyoming, primarily in the San Juan Basin.[186][187][188]