PETROLEUM
resides in the Arctic.
Extraction
Oil extraction is simply the removal of oil from the reservoir (oil pool). Oil is often
recovered as a water-in-oil emulsion, and specialty chemicals called demulsifiers are
used to separate the oil from water. Oil extraction is costly and sometimes
environmentally damaging, although Dr. John Hunt of the Woods Hole Oceanographic
Institution pointed out in a 1981 paper that over 70 per cent of the reserves in the world
are associated with visible macroseepages, and many oil fields are found due to natural
seeps. Offshore exploration and extraction of oil disturbs the surrounding marine
environment.
Oil spills
Crude oil and refined fuel spills from tanker ship accidents have damaged natural
ecosystems in Alaska, the Gulf of Mexico, the Galapagos Islands, France and many
other places.
The quantity of oil spilled during accidents has ranged from a few hundred tons to
several hundred thousand tons (e.g
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