Formation of Natural Gas

When we use natural gas powered heaters and stoves in our homes, we usually neglect to ponder the fact that these modern conveniences are made possible by a natural substance of ancient origin. Even the electricity supplied by utility companies often relies on natural gas for production. Natural gas, which is composed primarily of methane, is an important source of energy in the world today, burning cleaner and producing less harmful emissions than other fuels. With the widespread use and reliance on natural gas, one can easily forget that this key source of energy originated from organisms which lived millions of years ago.

Several differing theories attempt to explain the true origin of natural gas, though the most widely accepted explanation is that natural gas forms from the remains of ancient microorganisms as well as plant and animal matter that have undergone conditions of extreme heat and pressure over very long periods of time. As such organic matter is buried by increasing amounts of mud and sediment over time, the resulting pressure forces it further underground, compressing the matter and subjecting it to the high temperatures that exist deep within the earth. Intense compression and high temperature conditions cause carbon bonds in the organic matter to break down, a chemical transformation resulting in the formation of natural gas and other fossil fuels.

Another way natural gas is formed is by microorganisms known as methanogens. Methanogens are microscopic organisms which live in environments devoid of oxygen and chemically decompose organic matter, creating methane as a byproduct. Contrary to the natural gas formed by compression of organic matter under intense pressure at great depths, methane created by methanogens is typically found closer to the earth’s surface where the organisms live.

Once natural gas forms within the earth, its low density causes it to rise through the path of least resistance, often escaping the earth’s crust and dissipating into the atmosphere. But natural gas deposits that are sought for extraction by companies such as Western Pipeline Corporation form when impermeable rock “traps” the natural gas within the earth, preventing it from escaping and causing it to collect, creating a reservoir.

Natural gas is usually located within such reservoirs floating atop oil deposits, which have formed reservoirs in much the same way. However, deposits containing only natural gas are not unusual. Both the oil and natural gas may be extracted by drilling into the impermeable rock restricting the fossil fuels to the reservoir. The natural pressure already present within the reservoir allows the fossil fuels to escape on their own once the rock containing them is penetrated.

Once natural gas is extracted from the earth, it is treated (if necessary) and distributed to supply the energy on which much of the world relies.