Page 9 - 4822

Petroleum is a naturally occurring liquid found in rock
formations. It consists of a complex mixture of hydrocarbons of
various molecular weights, plus other organic compounds. It is
generally accepted that oil is formed mostly from the carbon rich
remains of ancient plankton after exposure to heat and pressure in
the Earth's crust over hundreds of millions of years. Over time, the
decayed residue was covered by layers of mud and silt, sinking
further down into the Earth’s crust and preserved there between
hot and pressured layers, gradually transforming into oil
reservoirs.

Early history
Petroleum in an unrefined state has been utilized by
humans for over 5000 years. Oil in general has been used since
early human history to keep fires ablaze, and also for warfare.
Its importance in the world economy evolved slowly, with
whale oil used for lighting into the 19th century and wood and coal
used for heating and cooking well into the 20th Century. The
Industrial Revolution generated an increasing need for energy
which was fueled mainly by coal, with other sources including
whale oil. However, it was discovered that kerosene could be
extracted from crude oil and used as a light and heating fuel.
Petroleum was in great demand, and by the twentieth century had
become the most valuable commodity traded on the world
markets.

Modern history
Imperial Russia produced 3,500 tons of oil in 1825 and
doubled its output by mid-century. After oil drilling began in what
is now Azerbaijan in 1848, two large pipelines were built in the
Russian Empire: the 833 km long pipeline to transport oil from the
Caspian to the Black Sea port of Batumi (Baku-Batumi pipeline),
completed in 1906, and the 162 km long pipeline to carry oil from
Chechnya to the Caspian.
At the turn of the 20th century, Imperial Russia's output of
oil, almost entirely from the Apsheron Peninsula, accounted for
half of the world's production and dominated international

9