Thermal maturation

Schimmelmann, A., Sessions, A.L., Mastalerz, M. (2006). Hydrogen isotopic (D/H) composition of organic matter during diagenesis and thermal maturation. Annual Review of Earth and Planetary Sciences, Vol. 34, pp. 501-533. 

Radke et al. [28] described an automated medium-pressure liquid chromatograph, now commonly called the Kohnen-Willsch instrument. At present, the method is widely used to isolate different fractions of soluble organic matter (for instance, as described in Reference 29 to Reference 31). A combination of normal phase and reversed-phase liquid chromatography has been used by Garrigues et al. [32] to discriminate between different aromatic ring systems and degrees of methylamine in order to characterize thermal maturity of organic matter. 

Although the data are not plentiful, it is clear that the hydrothermal solutions of sediment-hosted ridges and back-arc basin covered by sediment (Okinawa Trough) contain high amounts of ammonium (2.8-13.6 p.molal) (Scott, 1997). This means that ammonium was derived by thermal maturation reaction of organic matter in sediments by the following reactions (Gamo et al., 1991),... 

The mechanism of alkyl hydrogen exchange was not clarified, but a possible mechanism was postulated. Partial hydride abstraction by a Lewis acid site may have occured forming a carbocation-like species followed by exchange of a proton at a R-carbon. Such a mechanism predicts exchange to occur preferentially at methyl groups adjacent to the most stable carbocations (benzylic > 3° > 2° > 1°). This is consistent with the observed relative rates of epimerization of steranes during thermal maturation of sediments (83). 

Peters KE, Rohrbach BG, Kaplan IR (1981) Carbon and hydrogen stable isotope variations in kerogen during laboratory-simulated thermal maturation. Am Assoc Petrol Geol Bull 65 501-508... 

Standley, L. J., and B. R. T. Simoneit, Characterization of Extractable Plant Wax, Resin, and Thermally Matured Components in Smoke Particles from Prescribed Burns, Environ. Sci. Technoi, 21, 163-169 (1987). 

It has been postulated that odd-carbon preference is characteristic of bulk organic matter and that its disappearance results from thermal maturation processes as petroleum is being formed. However, as these... 

The chromatogram of the corresponding fraction from the Medicine River oil, Figure 12, shows the best peak resolution, and these peaks appear to represent the same benzothiophenes present in the other oils. This is believed to be a thermally mature oil, and it is therefore expected that the alkyl side chains would be reduced to methyl residues. The... 

Van Gijzel, P. Characterization and identification of kerogen and determination of thermal maturation by means of qualitative and quantitative microscopical techniques, in How to assess maturation and paleotemperatures (eds. Staplin, F. L. et al.) SEPM Short Course 7, p. 91, Tulsa OK, SEPM 1982... 

Figure 14. Variation in the carbon number distribution of the bicyclic terpenoid sulfides as a function of depth as shown by the m/z =183 fragmentograms from the SIR-GC/MS experiment. All traces are normalized to the most abundant peak. The oils vary from a heavy Cretaceous oil (Lloydminster) to a light Devonian oil (Leduc). Increasing thermal maturity results in the gradual loss of the isoprenoid side chain until in the Leduc the C13 compound dominates the distribution. Note the intensity distribution of the peaks. Minima occur at C12, C17, and C23. (Reproduced from Ref. 10 with permission. Copyright 1986, Pergamon Journals Ltd.)...

Schmoker J.W. (1984) Empirical relationship between carbonate porosity and thermal maturity An approach to regional porosity prediction. AAPG Bull. 68, 1697-1703. 

Koopmans M. P., Schaeffer-Reiss C., DeLeeuw J. W., Lean M. D., Maxwell J. R., Schaeffer P., and Sinninghe Damste J. S. (1997) Sulphur and oxygen sequestration of n-C37 and n-C38 unsaturated ketones in an immature kerogen and the release of their carbon skeletons during early stages of thermal maturation. Geochim. Cosmochim. Acta 61, 2397-2408. 

Boreham C. J. and Powell T. G. (1991) Variation in pyrolysate composition of sediments from the Jurassic Walloon coal measures, eastern Australia as a function of thermal maturation. Org. Geochem. 17, 723—733. 

Venkatesan M. L, Ohta K., Stout A., Steinberg S., and Oudin J.L.(1993) Diagenetic trends of lignin phenols in Mahakam Delta coals correlation between laboratory thermal maturation and natural samples. Org. Geochem. 20, 463-473. 

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