Drilling for Natural Gas

Описание: The exploration for and production of natural gas is very similar to that of petroleum. In fact, natural gas is commonly found in the same reservoirs as petroleum. Because natural gas is lighter, it is often found on top of the oil. And like oil, some natural gas flows freely to wells because of the natural pressure of the underground reservoir forces the gas through the reservoir rocks. These types of gas wells require only a Christmas tree, which is a series of pipes and valves on the surface that are used to control the flow of gas. Only a small number of these free-flowing gas formations still exist in the U.S. gas
fields. Most now need some type of pumping system to extract the gas still trapped in the underground formation. One of the most common is the horse head pump, which
rocks up and down to lift a rod in and out of a well bore, bringing gas and oil to the surface. Often the fl ow of gas through a reservoir can be improved by creating tiny cracks in the rock, called fractures, that serve as open pathways for the gas to fl ow. In a technique called hydraulic fracturing, drillers force high pressure fl uids (like water) into a formation to crack the rock. A propping agent, like sand or tiny glass beads, is added to the fluid to prop open the fractures when the pressure is decreased. For more information, go to the USDOE guide at http://www.fossil.energy.gov/educatio...
This is clipped from the 1959 film, These Are My People, produced by the Columbia Gas System and available at the Internet Archive.