Fracking
The modern fracturing technique, called 'horizontal slickwater fracturing', was first used in 1998. It made the extraction of shale gas economically practical. The energy from the injection of a highly pressurized fluid creates new channels in the rock. This increases the extraction rates and recovery of hydrocarbons, which are used for fuel. In 2010 it was estimated that 60% of all new oil and gas wells worldwide were being hydraulically fractured. As of the year 2012, 2.5 million hydraulic fracturing actions have been done on oil and gas wells worldwide, more than one million of them in the United States.