Since Fracking was first introduced to the oil industry, it has caused unrest among the population for a number of reasons. First of all, studies have shown that fracking does cause small earthquakes, but some experts claim that these earthquakes relieve pressure that would have caused bigger, more damaging earthquakes. Fracking also uses large amounts of water that contain many environmentally damaging materials. Fracking operations can cause tremendous environmental harm, and some regulators believe that current regulations are not strict enough to prevent this harm. Despite all the difficulties that Fracking causes, it also makes the price of generating electricity with natural gas about the same as generating electricity with coal. This diversifies the U.S.'s energy portfolio.