Solid Earth System

Coal solid, “rocky” material derived from land plants source: bogs and swamps high carbon content (50-90%) lump of coal
Petroleum (Crude Oil) liquid derived from marine plankton source: marine sediments mostly hydrocarbons, e.g.
octane
Natural Gas gaseous version of oil mostly methane methane

Most organic material is rapidly oxidized
(e.g. by bacteria) into CO
2 and H and is returned to the biosphere.
2
0
Situations that lead to long term (millions of years) preservation are rare.
In addition to preservation, creation of fossil fuels requires removing water
(dehydration) and reduction (removing oxygen) from organic matter.

other sedimentary rocks other sedimentary rocks

World distribution of coal deposits

World distribution of organic-rich sediments

linear molecules branched molecules ring molecules
About 30% of this crude oil consists of molecules that distill below 375 ° F, and thus have 12 or fewer carbons

highest organic carbon concentration at sedimentation rates of 10-100 cm/ka

Airgun and hydrophone arrays on an exploration vessel

Map of burgan field – note overall “dome” structure produces a very large structural trap

Map of burgan field – note overall “dome” structure produces a very large structural trap

Production history of the Magnus field in the North Sea

Cumulative production increases with time, but more and more slowly, until the field is exhausted