See Where does Petroleum Come from

We are going to talk Origin of petroleum
But First  I will talk
about the origin of the world itself, Rock outcrop at the surface of the earth
have been producing oil for century and this oil was known as rock oil, Because
at that period oil was seeping out the rock, But at the middle of 19 century
some body called the word Petroleum, Petro is greak word meaning rock and leum
is latin word meaning oil and they combine these two word called petroleum.
Then become popular word and eventually the word adopted by industry itself and
now is known as petroleum industry
 Where does petroleum come from?
 There are two theory about where petroleum come from
·        
Organic
theory :
State that oil was developed over millions of years from organic
materials from remains of animals and plants that were once alive, the proteins
life floaded in the sea like plankton and algae then die and fed to the bottom
of the ocean.
·        
Inorganic theory In this teory the source of oil
is from chemical reactions between minerals, In the laboratory scientists have
been able to make methane gas by applying heat under high pressure to minerals
even though a very small percentage of oil today may have developed from in
organic chemical reactions between minerals the source of most our oil appear
to be the result of organic decomposition.
These decomposition is the decay of the
remains of animals and plants that died millions of years ago
                When
am talking about animals that was died and generate oil am talking about tiny
microscopic animals that live in the sea eg plankton and algae
    These animals die
under special circumstances, and what do I mean by that?
         As you know
when most animals die other animals and bacteria arrive to consumes the remains
living nothing. In the shallow water where these animal live, sweep current
come on and push these down to where there is no enough oxygen to live and so
they die. These animals went from an aerobic environment where there is plenty
of oxygen to an anaerobic environment where there is little oxygen where all
die at the same time.
In an anaerobic there also not enough oxgen for most animals
microbs or bacteria to come along and eat the remains of planktons and algae so
the just lie there until the get buried by particles of silt and sand.
Over period of millions of years these layers of remains in
sand and silt particles are buried and curved by more layer until first layer
become very deep. All the way of these layer to press down and squeezed caused
increased in pressure and temperature until the sedimentary layers are formed
into shale, sediment change into rock, and little dead microbs get cooked into
hydrocarbon.
These is the theory of how petroleum and coal is made.
Oil is made from animal like plankton
Coal is made from vegetation like plants

Gas is made from deeper formation where microbes are cooked
longer