Where is oil found?

Oil is not found in underground lakes. It is commonly found enclosed in the interstices between the grains of sand that form the rocks called “sandstones”, which can be of marine, fluvial, glacial or lacustrine origin.

It is considered that, after its formation, the oil was expelled, by the weight of the sediments that had been deposited on the fine-grained rocks (clays and silts) in which it had been formed, towards a more porous rock, of thicker grain, in the pores of which it could accumulate. This displacement of oil, from its rock of origin to the rock in which we find it today, is called “migration of oil”. The rock in which we find it is called the reservoir rock. The rock on which we assume it was formed is called “mother rock.”

Is oil the same as hydrocarbon?

Organic matter from animals, plants and microorganisms was covered by layers of other sediments and, over time, under special conditions of temperature, pressure, was transformed into hydrocarbons, which are the result of organic decomposition, and whose molecules are formed by carbon and hydrogen, and in a much smaller proportion of sulfur, oxygen and nitrogen, as well as smaller parts of iron, chromium, nickel and vanadium. Crude oil is extracted from oil.