The Barnett Shale is more than 7,000 feet below the surface and is comprised of dense non-permeable rock. According to Dr. Ken Morgan, a geologist at Texas Christian University, “Solid hard rocks that are 7000 feet down don’t subside. You have more than a mile of solid rock that holds it all up. Subsidence occurs when you have loose, soft materials like in Houston (sands, clays, etc.) but not in cemented hard rocks like the Barnett Shale.”

Facts About Natural Gas
Natural gas is a cleaner burning energy source than other fossil fuels. Its use is becoming increasingly popular as an alternative fuel. Natural gas is used for heating, generating electricity and as a transportation fuel. However, it is also a raw material used in things such as plastics, medicines, fertilizers and dyes. According to the U.S. Department of Energy, 22 percent of energy consumption in America comes from natural gas. Because natural gas is plentiful in the U.S., using natural gas over oil may help reduce our dependence on foreign energy sources. (source: Department of Energy)
When natural gas comes out of the ground, it is a mixture of gases and other substances, being predominantly methane. The natural gas that consumers use is made almost entirely of methane. Raw natural gas is produced from natural gas wells, oil wells or condensate wells.
Most all of the natural gas wells in the Barnett Shale in Tarrant County produce gas that has a specific gravity of less than 1.0 which means that it is lighter than air and does not accumulate on the ground.
Why is natural gas a cleaner fuel?
Natural gas is the cleanest of all the fossil fuels. Composed primarily of methane, the main products of the combustion of natural gas are carbon dioxide and water vapor, the same compounds we exhale when we breathe. Coal and oil are composed of much more complex molecules, with a higher carbon ratio and higher nitrogen and sulfur contents.
This means that when combusted, coal and oil release higher levels of harmful emissions, including a higher ratio of carbon emissions, nitrogen oxides (NOx), and sulfur dioxide (SO2). Coal and fuel oil also release ash particles into the environment, substances that do not burn but instead are carried into the atmosphere and contribute to pollution.
The combustion of natural gas, on the other hand, releases very small amounts of sulfur dioxide and nitrogen oxides, virtually no ash or particulate matter, and lower levels of carbon dioxide, carbon monoxide, and other reactive hydrocarbons.




