10,323
edits
Changes
Jump to navigation
Jump to search
Line 31:
Line 31: − +
→Limitations
* Only a few molecular fossils can be correlated to biotic antecedents confined to a narrow range of environments.
* Only a few molecular fossils can be correlated to biotic antecedents confined to a narrow range of environments.
Thus, Treibs'<ref name=ch17r89>Treibs, A., 1934, On the occurrence of chlorophyll derivates in an oil shale of the Upper Triassic Period: Annales Chimie 509, p. 103–114.</ref> discovery that derivatives of chlorophyll are widespread in oils is not useful in defining paleoenvironments because chlorophyll is environmentally ubiquitous. Volkman<ref name=ch17r93>Volkman, J., K., 1986, A review of sterol markers for marine and terrigenous organic matter: Organic Geochemistry, vol. 9, p. 83–99, DOI: [http://www.sciencedirect.com/science/article/pii/0146638086900896 10.1016/0146-6380(86)90089-6].</ref> dispells an earlier concept that an abundance of C<sub>29</sub> sterols is evidence of terrigenous organic matter by finding abundant C<sub>29</sub> sterols in lacustrine environments.
Thus, Treibs'<ref name=ch17r89>Treibs, A., 1934, On the occurrence of chlorophyll derivates in an oil shale of the Upper Triassic Period: Annales Chimie 509, p. 103–114.</ref> discovery that derivatives of chlorophyll are widespread in oils is not useful in defining paleoenvironments because chlorophyll is environmentally ubiquitous. Volkman<ref name=ch17r93>Volkman, J. K., 1986, A review of sterol markers for marine and terrigenous organic matter: Organic Geochemistry, vol. 9, p. 83–99, DOI: [http://www.sciencedirect.com/science/article/pii/0146638086900896 10.1016/0146-6380(86)90089-6].</ref> dispells an earlier concept that an abundance of C<sub>29</sub> sterols is evidence of terrigenous organic matter by finding abundant C<sub>29</sub> sterols in lacustrine environments.
==Methodology==
==Methodology==