Thermal Maturity of Organic Matter

In areas where the rocks have been subjected to complex folding and faulting or have been intruded by igneous rocks, the geothermal maturity of the oil shale should be evaluated for proper determination of the economic potential of the deposit. 

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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. 

Rowan, E. L., Goldhaber, M. B., and Hatch, R. R., 1996, Constraints on the thermal and burial history of the Illinois Basin from fluid inclusions and thermal maturity of organic matter in Geological Society of America, 28th annual meeting, p. 387. 

Michels R, Landais P, Elie M, Gerard L, Mansuy L (1992) Evaluation of factors influencing the thermal maturation of organic matter during confined pyrolysis experiments. Am Chem Soc Division Fuel Chem Preprints 37 1588-1594 Nelson RA (1985) Geologic analysis of naturally fractured reservoirs. Gulf, Houston, 320 PP... 

Dell Abate, M. T., Canali, S., Trinchera, A., Benedetti, A., and Sequi, P. (2000). Thermal methods of organic matter maturation monitoring during a composting process. J. Ther. Anal. Cal. 61, 389-396. 

Yamamoto et al., 2007), including evaluation of the level of maturation of organic matter in composts (Dell Abate et al., 2000) and evaluation of relative soil health (Nunez-Regueira et al., 2006) through use of thermal analysis to evaluate relative microbial activity. Table 18.3 summarizes materials, methods employed, and relevant citations. 

Fig. 6.16. Burial, thermal, and maturation histories of the sedimentary section of the Akfadou region, Ghadames Basin. The greater volume of sedimentation compared with the variant of Oued el-Mya Basin in Fig. 2 in Makhous et al. (1997) led to the greater level of maturation of organic matter in Silurian rocks, despite a moderate level of Hercynian uplift...

Baker E. W., Huang W. Y., Palmer S. E. and Rankin J. G. (1977) Mass and electron paramagnetic resonance spectrometric analyses of selected organic components of Cretaceous shales of marine origin. Symposium on Analytical Chemistry of Tar Sands and Oil Shale. Amer. Chem. Soc., New Orleans, March 20-25, 1977, 739-752. Baskin D. K. (1997) Atomic H/C ratio of kerogen as an estimate of thermal maturity and organic matter conversion. Am. Assoc. Petrol. Geol. Bull. 81, 1437-1450. 

Organic acids detected in waters associated with petroleum may be classified as aliphatic carboxylic acids or aromatic carboxylic acids. With respect to generation of these acids from thermally maturing sedimentary organic matter, the aliphatic carboxylic acids have been the most studied. These acids may consist of straight, branched, or cyclic aliphatic groups that are either saturated or unsaturated and contain one or more carboxylic acid groups. Acyclic, saturated, mono- and di-carboxylic acids are the most commonly detected and emphasis will be placed on these acid types. 

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. 

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),... 

Table I summarizes the indicated maturation levels of organic matter from the Kettle Point, Marcellus and Whitby Formations and equivalents in various areas. Using Figure 4, these may be related to thermal maturation. Only a few samples have been ex-...

The transformations reviewed in Section 5.5 are potential maturity indicators.The most useful reactions are those in which only one of the pair of components is present initially in immature sediments, so that the extent of the transformation can be attributed entirely to thermal maturation (the kinetics of the transformation are also simpler Box 5.4). Such reactions include isomerization of pristane at C-6 and C-10, of steranes at C-20 and of hopanes at C-22, and also the aromati-zation of C-ring monoaromatic steroidal hydrocarbons. A number of molecular maturity parameters are shown in Fig. 5.47, together with some bulk maturity measurements.The correlation of values is approximate and varies with the type of organic matter present, its potential for generating petroleum and its heating rate. 

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