Oilfields.

[WBA1955]

A thing that has always puzzled me. Think of everything on earth that requires oil to operate day after day, year after year.
How vast must the lakes of oil be? As vast as the oceans?
How did the first people who tapped oil know how much there was to produce automobiles, trains, lorries and planes en masse.
They must have been confident that the supply was there for many years into the future.
I still can't get my head around how much oil there must be.
So many questions in so short a life.

[Dubbag]

A thing that has always puzzled me. Think of everything on earth that requires oil to operate day after day, year after year.
How vast must the lakes of oil be? As vast as the oceans?
How did the first people who tapped oil know how much there was to produce automobiles, trains, lorries and planes en masse.
They must have been confident that the supply was there for many years into the future.
I still can't get my head around how much oil there must be.
So many questions in so short a life.

In parts of Northern Iraq the oil is so plentiful that it seeps out through fissures in the rock on the surface. The locals have been using it for thousands of years...The pitch that was used int he day of Noah...was most likely the surface oil bitchinum...

In the early days they had no idea of the structure of the deep underground oil fields....until geologists began to understand that the topography of the ground underneath is usually similar to the ground on top and that if you had a cap rock (stone) in pace it could stop the oil migrating to the surface like in Northern Iraq.
Once they discovered the structure of oil fields it became easier to work out by pressure how much oil was possibly down there.
They use the three 'Ps"....Proven reserves...which will come out of the ground through pressure. Probable reserves...which will come out of the ground with some assistance, like re-injection of water down through another bore hole to maintain pressure.. Possible reserves are the reserves that may be extracted at a later date when technology improves.

Oil and gas is found only in certain areas of the world. The fundamentals of understanding an oil field differs from region to region...
This is factored by the standard..."API"...American Petroleum Institute. this measures the flow of the oil discovered...a low API of less then say 22" is regathered as heavy oil and takes more refining and more costly....but can affect how much oil is in the field.....an API of over 35" could almost be put straight into your car, it is that pure and lite....which is costlier......but it also affects how much oil is in the ground....
Structures of oil fields is an interesting subject in itself....information here might help 55"
https://oilandgasoverview.com/what-is-the-api-gravity-of-crude-oil/

[mickd1961]

A subject that fascinates me as well Des.

Provable reserves of oil seem to give us another 50 years of supply.

Although there is more oil still to be discovered there will become a point where it’s no longer financially viable to extract.

When you consider 7/10 of the World is covered by water and that much of the oil sits underneath it it just adds to the challenge.

The other thing that always fascinated me is the amount of living matter that has had to have been for these reserves to have been created and the length of time for this to happen.

Same with beaches, just the sheer volume of material that has had to be worn down to create all the sand on this planet.

[Dubbag]

Millions of years in the making.....stored decomposed once living material with huge pressure and heat over eons.
Most fields are divided into three main parts....water....oil...and gas......
The decomposition over time, along with the pressure and heat generated allows the material to break into its parts as with most living things today...
The deserts of Saudis Arabia and the likes were once gigantic forests millions of years ago. But today they are just deserts.
But it is all about timing as usual.......In Ireland we have the biggest turf bog land in all of western Europe.....in a few more millions of years it would remain half decomposed but not enough pressure to turn it into coal....so it stays as peat...still a fuel.
But the right ingredients haven't been met yet....

[Dubbag]

And of note recently by the oil industry of recent...is that many fields are degrading quicker then thought....some fields in Arabia have been down graded substantially....oil migrates and can move.....The oil field itself is not an underground lake as envisaged by many but rather is a huge area of soft sand bearing structure which allows the hydrocarbons to nestle in the spaces between the spheroidal sand grains.....