cracking of oil वाक्य

Although kerogen cracking decomposition is a source of oil and gas from the Barnett Shale, the principal source of gas in the Newark East Field is from cracking of oil and bitumen.
The term has also been applied to the decomposition of organic material in the presence of superheated water or steam ( hydrous pyrolysis ), for example, in the steam cracking of oil.
:As far as I'm aware, propane-as a pure substance that has to be derived sequentially by cracking of oil-is substantially more expensive to produce than raw, methane-based natural gas which is extracted directly in a near-usable form from gas wells.