Hydrocarbons maturation

Interpretation of the timing of dolomitization is important in a variety of studies, including hydrocarbon maturation and migration and porosity development. In Chapter 10 we discuss further the dolomitization process as a clue to ocean-atmosphere evolution. 

Figure 8.34. Hypothetical porosity-depth curves for various diagenetic situations. A. "Normal" burial curve of chalk sequences. B. A typical curve stemming from porosity changes brought about by dissolution and cementation processes during meteoric zone diagenesis. C. A scenario for late stage porosity development brought about by a dissolution event related to hydrocarbon maturation and destruction. D. Porosity preservation resulting from conditions of overpressuring. (After Choquette and James, 1987.)...

Farrimond P., Bevan J.C., Bishop A.N. (1996) Hopanoid hydrocarbon maturation by an igneous intrusion. Org. Geochem. 25, 149—64. 

Fig. 2. Variation in maturity of the sample set studied based on light hydrocarbon maturity parameters (based on Thompson 1983).

Fig. 7. Cross plots of calculated vitrinite reflectance equivalent biomarker maturity (Ro Ts) and light hydrocarbon maturity (Schaefer Ro) effectively indicates that almost all oils are mixtures in the true sense with a range of maturities of charge being present together in the trap. Only the flagged oils (red dots) may represent single maturity point charges, but even here that is doubtful. A mass fraction maturity concept better describes the maturity of an oil.

Me Bride EF (1989) Quartz cement in sandstones a review. Earth Science Reviews 26 69-112 McKenzie DP (1981) The variation of temperature with time and hydrocarbon maturation in sedimentary basins formed by extension. Earth and Planetary Science Letters 55 87-98 Meunier JD, Sellier E, Pagel M 1990) Radiation-damage rims in quartz from uranium-bearing sandstones. J Sediment Petrol 60 53-58 Millot G (1964) G6ologie des argiles. Masson et Cie, Paris, p 499... 

Isotopic equilibrium between 2 and CH4 does not appear likely in Taranaki. In TVZ apparent isotopic temperatures are higher than reservoir temperatures but show fair correlation. This may relate both to a hydrocarbon maturity effect and to a source effect but this does not fiiUy explain the 8 C(CH4) and S C(C02) distribution within some fields. 

McKenzie D. T. (1981) The variation of temperature with time and hydrocarbon maturation in sedimentary basins formed by extension. Earth Planet. Set Lett. 55, 87-98. 

Palciauskas, V.V. Domenico, P.A. Microfracture development in compacting sediments relation to hydrocarbon-maturation kinetics. AAPG Bulletin 1980, 64, 927-937. 

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