Information AboutKerogen |
| CATEGORIES ABOUT KEROGEN | |
| soil science | |
| petroleum products | |
Distinguish from Keratin . Kerogen is a mixture of Solvent s because of the huge Molecular Weight (upwards of 1,000) of its component compounds. The soluble portion is known as Bitumen . When heated to the right temperatures in the Earth's Crust , some types of kerogen release Oil or Gas , collectively known as Hydrocarbon s ( Fossil Fuel s). When such kerogens are present in high concentration in rocks such as Shale , and have not been heated to a sufficient temperature to release their hydrocarbons, they may form Oil Shale deposits. Kerogen from the Green River Formation oil shale deposit of western USA has the Chemical Composition C215H330O12N5S.Teh Fu Yen and George V. Chilingarian (1976) ''Oil Shale'', Amsterdam, Elsevier TYPES ''Labile'' kerogen breaks down to form heavy Hydrocarbon s (i.e. Oil s), '' Refractory '' kerogen breaks down to form light hydrocarbons (i.e. gases), and '' Inert '' kerogen forms Graphite . A Van Krevelen Diagram is one example of classifying kerogens, where they tend to form groups when the ratios of hydrogen to carbon and oxygen to carbon are compared. Example of a Van Krevelen diagram Type I
Type II
They all have great tendencies to produce petroleum and are all formed from lipids deposited under Reducing conditions. Type II-Sulfur
Type III
Kerogen Type III is formed from terrestrial plant matter that is lacking in Lipid s or waxy matter. It forms from Cellulose , the Carbohydrate Polymer that forms the rigid structure of terrestrial plants, Lignin , a non-carbohydrate polymer formed from phenyl-propane units that binds the strings of cellulose together, and Terpene s and Phenol ic compounds in the plant. Most of the Biomass that eventually becomes Petroleum is contributed by the Bacteria and Protist s that decompose the primary matter, not the primary matter itself. However, the lignin in this kerogen decomposes to form phenolic compounds that are toxic to bacteria and protists. Without this extra input, it will only become Methane and/or Coal . Type IV (residue)
Type IV kerogen contains mostly decomposed organic matter in the form of Polycyclic Aromatic Hydrocarbon s. They have no potential to produce hydrocarbons. ORIGIN OF MATERIAL Terrestrial material The type of material is difficult to determine but several apparent patterns have been noticed.
Extraterrestrial material
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