Natural gas, indispensable in industry and urban infrastructure, is an invaluable wealth of subsoil formed in underground cavities in ancient times. Humanity depends on gas no less than it does on oil, and besides, it is a fairly clean fuel, which practically does not pollute the atmosphere with harmful emissions. In many countries, natural gas is even more widespread than oil and internal combustion engines operating on products of its processing.
In nature, it is found both separately from oil and with it. In the second case, it usually forms a semblance of a gas cap over oil deposits. Natural gas was formed due to the decomposition of organic matter without air access, at a time so ancient that it is difficult to imagine. Natural gas consists of different substances, but most of all it contains methane. On average, it accounts for from 70 to 98% of the gas mixture. Despite this, natural gas does not have its own smell. Strongly smelling substances are specially added to it so that a gas leak can be noticed in time.
Since 1971, the gas crater of Darvaz, which is also called the “Gates of the Underworld”, has been continuously burning in Turkmenistan. Then geologists decided to set fire to natural gas, but they made mistakes in thinking, thinking that it would soon burn and go out. The fire is still burning there. Science believes that the formation of natural gas requires more pressure than the formation of oil. This is probably why gas fields are usually found at greater depths than oil fields. Methane, which forms its basis, is the third most abundant substance in the Universe, after hydrogen and helium.
All developed fields of pure natural gas are located at a depth of more than 1 km. And near Novy Urengoy, it is mined from a depth of about 6 km. Pure natural gas self-ignites when heated to 650 degrees. The specific gravity of natural gas is lower than the specific gravity of air, almost doubled (1.8 times), so when it leaks, it always tends upwards. The first place in the world for its mining is held by Russia and the USA. They account for about 30% of the entire global gas industry. Every year, more than 3.5 trillion cubic meters of natural gas is extracted from the Earth’s interior.
In some US states, in order to make it easier to detect natural gas leakage, a harmless substance with a smell of rotten is added to it. Griffon vultures in the desert locality immediately smell it and flock in search of prey to the leak, which allows it to be localized. People learned to use natural gas for their own purposes long ago. About 1900 years ago, one of the rulers of Ancient Persia ordered to build a kitchen on the place where its jet was leaving the ground. She was set on fire, and the fire in the kitchen burned without stopping. The total length of gas pipelines laid across Russia exceeds 870 thousand kilometers. This is about twice the distance to the moon. Not always in gas fields it is separate from other substances. Often the gas is dissolved in oil or water.
