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Hey to all experts out there!

I always read about either a gas field or oil field being discovered and I was wandering why this differentiation occurs. Is it always so that when gas is formed in a reservoir no oil remains... (I know oil forms before gas, right?). But are there actually fields that have both gas and oil in them? And how does this differentiation actually occur? When do we find gas and when do we fid oil? Is this related to temperature on the most part?

Hope to hear from you and thank you very mich!!

Well, oil comes out from the ground. It was made over many years by pressure being applied on natural substances. Today oil is found in permeable rock formations while natural gas comes from a wide range of resources. It can be found underground, often associated with oil fields. It can also be found by itself in gas fields. It is also produced through natural procedures in landfills, bogs & sewage or fertilizer places.

Oil comes out from the ground. It was created over millions of years by pressure being exerted on organic substances. Today it is found in porous rock formations. Sometimes there will be a large open space underground that is filled with a ‘sea of oil.

Natural Gas comes from a variety of sources. Sometimes it is found underground, often associated with oil fields. It can also be found by itself in natural gas fields. It is also produced through natural processes in bogs, landfills, and sewage or manure dumps.