As you drive to this site, you will notice the land
criss-crossed with oil pipelines and evidence of oil and gas wells,
flares and processing plants all around. This is evidence of this
region being formed on the base of a prehistoric sea. You will also
see evidence of this in the rounded pebbles (evidence of water
action in the past) and layered outcrops (evident close to the
University – and the hillock you are now standing on). This i oil
field forms part of the Greater Ghawar uplift, which also includes
fields in Saudi Arabia and Qatar. Oil and "pitch" has been evident
in the Middle East for a long time, even two biblical references to
oil exist; Noah sealing his ark with pitch and Moses' mother
sealing his crib with pitch and bitumen when floating the baby on
the Nile River. A so-called fossil fuel, petroleum is believed by
most scientists to be the transformed remains of long dead
organisms. The majority of petroleum is thought to come from the
fossils of plants and tiny marine organisms. Larger animals might
contribute to the mix as well.
"Even some of the dinosaurs may have gotten involved in some of
this," says William Thomas, a geologists at the University of
Kentucky. "[Although] I think it would be quite rare and a very
small and insignificant contribution."
But another theory holds that more oil was in Earth from the
beginning than what's been produced by dead animals, but that we've
yet to tap it.
How it works
In the leading theory, dead organic material accumulates on the
bottom of oceans, riverbeds or swamps, mixing with mud and sand.
Over time, more sediment piles on top and the resulting heat and
pressure transforms the organic layer into a dark and waxy
substance known as kerogen.
Left alone, the kerogen molecules eventually crack, breaking up
into shorter and lighter molecules composed almost solely of carbon
and hydrogen atoms. Depending on how liquid or gaseous this mixture
is, it will turn into either petroleum or natural gas.
So how long does this process take?
Scientists aren't really sure, but they figure it's probably on
the order of hundreds of thousands of years.
"It's certainly not an instantaneous process," Thomas told
LiveScience. "The rate at which petroleum is forming is not going
to be the solution to our petroleum supplies."
To claim this cache the following is required:
1) A photo with cacher and GPSr looking over the plain below.
OPTIONAL
2) Describe the valley below (to the south) you and identify a
number of aspects associated with the oil & gas reserves in the
area.
3) Give a short description of one way in which an oil reservoir
may be formed, explaining especially the geology that ensures that
the oil can be extracted.
4) Give your interpretation on how coal and oil fields differ in
formation.
5) Give a brief explanation of the "Peak Oil" theory.
6) Give some observations about how CO2 emissions, mainly from
fossil fuel combustion, are contributing to global climate
change.
