Major shale gas depositshave been identified in Pennsylvania and elsewhere in the US. Tom Gjelten, for NPR, describes how new drilling techniques makes extraction economically viable:
In recent years, natural gas producers in the United States have struggled, mostly in vain, to be taken more seriously in the energy world. Big oil companies like Exxon had concluded that natural gas reserves in the United States were not sufficiently abundant to warrant big investments in exploration and drilling. When small independent gas producers argued otherwise, they were often ridiculed.