I would like to know how crude oil gets so fare under ground when it's lighter than everything that covers it?

Answer 1

The materiel that crude oil is made from is overlaid by material that sometimes becomes impearmeable and prevents the migration of fluids, after formation, to the surface. This is what petroleum geologist search for in subsurface exploration. When these types of formations are located they can drill and extract the crude oil. TYhe following is an extract from the enclosed web site for you to further research.

Because oil is a relatively light liquid, it will migrate above denser fluids, such as water, unless confined in what geologists call a hydrocarbon trap. A hydrocarbon trap consists of porous rock that acts as sort of an oil-holding sponge and a roof of non-permeable rock to prevent oil from moving upward.

Answer 2

Geological processes cause the rock that holds the oil (commonly known as 'shale') downwards into the earth. Once oil is formed (typically tkaing upto 200million years, also needs just the write conditions, not to hot and hot too cold) oil being lighter than the surrounding rock does indeed work its way upwards. until it hits a geological brick wall; a non - porous rock

Essencially not allowing anything through it (such as an old lava flow, or most metamorphic rocks - also some sedimentry) this traps the oil. when we go prospectering we drill through this hard non porous rock breaking the seal and causing the oil (under pressure) to rush to the surface.

Hope this helps, and to any creationsits, it really didnt happen like that.

Answer 3

Ok fill a glass or jug or something with some water hold it under the water and place something heavy on top,instant recreation,the weight and pressure traps the air (oil) in a contained environment,as time goes by the hard enclosure is worn away and the oil is allowed to escape.

If you mean how it got there in the first place then it was debris animal/plant ect. that was buried and eventually rotted under the ground,by this time other layers had built on top of it so it was trapped despite being lighter than the surrounding objects.

Answer 4

It doesn't start out as petroleum. It forms in several steps. First, organic material,such as the remains of marine plankton, accumulates. The environment in which it accumulates is one that allows the preservation of organic muck. Then, the muck gets buried under more sediment. For the right chemical reactions to occur to produce petroleum, the hydrocarbon-rich muck layers need to be buried fairly deeply in order to raise temerature and pressure to just the optimum thresholds. These depths are also enough to cause lithification and cementation of overlying and underlying sediment layers---turning them into sedimentary rocks. Because the newly forming crude oil and natural gas are not very dense, they will start migrating "up" if they find a pathway through fractures or permeable rock layers. Sometimes the oil gets all the way to the surface and you will find evidence of this in tar seeps, for instance. But, sometimes it gets trapped beneath an impermeable rock layer such as shale. Buried oil traps are what petroleum geologists try to find for their companies. Buried anticlines or domes (downward curving folds in the rocks) are often good oil traps.

Answer 5

Interesting question: I believe in the abiotic theory of "oil" production. Oil and gas are "produced" by the earth through pressure and temperature actions over time.
Unlike coal - which goes from peat bogs to compressed peat to brown coal to bituminous coal to anthracite coal - all progressively harder - there is no obvious line for oil.
Besides TV commercials - no one has proven that oil comes from dinosaurs - how many dinosaurs really existed and did dinosaurs really have particular dinosaur grave-yards where they all went when ready to die? (see source below)
As I said before - The abiotic theory says that the earth created gas and oil in some kind of process using time, pressure and temperature. From this point the some people believe that the oil fills the fissures and cracks in rocks and eventually comes to the surface.
What is interesting, like the dinosaur theory, no one has proven this theory to be totally accurate. But I believe it is a better theory than the dinosaur hoax that has been perpetuated for decades.

Answer 6

Crude oil was formed in the carboniferous period, in hot humid places such as swamps. The areas must be anaerobic to prevent the plant matter being decayed. It is then slowly covered by other sediments. The increase in heat and pressure causes metamorphism and the plant matter changes state.
The whole process is called Diagenesis or Lithification.

Answer 7

It is formed from solid materials (trees, etc.) like coal is and is normally in porous rock formed from sand (lots of little organisms) Like in a marsh.
It is capped over with non-porous materials, like salt beds and slate (hardened clay). as when the water level changes and the ocean or rivers deposit sediment on top.
Multiple events bury the layer of oil sand under heavy rock.
The oil tends upward, usually above water or saltwater and gets trapped under curved rock layers.

Answer 8

Here is my guess, crude oil comes from living things that were alive many many years ago....they died.....they were covered up by land, water, errosion, sedimentation.....then after many years they became oil. Which is why it is under ground.

Answer 9

Creationists would say because God put it there... which does rather beg the question, why is it all under the Middle East, Allah's country!?