Comment: “Shale gas” is usually found in compact, low-permeability rocks deep beneath the surface. Reserves of this gas are very substantial and well distributed over the globe: they are estimated to represent between 120 and 150 years’ worth of natural gas supply at the current rate of consumption. While geologists have known for decades that shale gas existed deep beneath many areas of the North American continent, traditional vertical oil and gas drilling methods were able to access only a small fraction of the gas within these formations. But recently, operational efficiencies and proven technology have come together to make shale gas both accessible and economically competitive.
The link below will drive you to a dynamic and comprehensive presentation of the “shale gas” drilling and production process.