Resource Availability
The world's oil supply is fixed because petroleum is naturally formed far too slowly to be replaced at the rate at which it is being extracted. Over many millions of years, plankton, bacteria, and other plant and animal matter become buried in sediments on the ocean floor. When conditions are right – a lack of oxygen for decomposition, and sufficient depth and temperature of burial – these organic remains are converted into petroleum compounds, while the sediment accompanying them is converted into sandstone, siltstone, and other porous sedimentary rock. When capped by impermeable rocks such as shale, salt, or igneous intrusions, they form the petroleum reservoirs which are exploited today.
Read more about this topic: Oil Depletion
Famous quotes containing the words resource and/or availability:
“Helping children at a level of genuine intellectual inquiry takes imagination on the part of the adult. Even more, it takes the courage to become a resource in unfamiliar areas of knowledge and in ones for which one has no taste. But parents, no less than teachers, must respect a child’s mind and not exploit it for their own vanity or ambition, or to soothe their own anxiety.”
—Dorothy H. Cohen (20th century)
“Since ... six weeks ago, there has been no day in which I have not had letters and visits on the subject of my nomination for the Presidency.... I say very little. I have in no instance encouraged any one to work to that end.... I have said the whole talk about me is on the score of availability. Let availability do the work then.”
—Rutherford Birchard Hayes (1822–1893)