A chemical kinetic model of vitrinite maturation and reflectance

doi:10.1016/0016-7037(89)90136-1

Geochimica et Cosmochimica Acta

Volume 53, Issue 10, October 1989, Pages 2649-2657

https://doi.org/10.1016/0016-7037(89)90136-1 Get rights and content

Abstract

A chemical kinetic model is presented that uses Arrhenius rate constants to calculate vitrinite elemental composition as a function of time and temperature. The model uses distributions of activation energies for each of four reactions: elimination of water, carbon dioxide, methane and higher hydrocarbons. The resulting composition is used to calculate vitrinite reflectance via correlations between elemental composition and reflectance. The correlations are derived from published measurements. The model is valid for %Ro values from slightly less than 0.3 to slightly greater than 4. Model calculations are compared to published vitrinite data from both laboratory experiments and sedimentary columns where adequate thermal histories are available. Calculated and measured %Ro values generally agree within 0.1 at low rank and 0.4 at high rank, which is comparable to uncertainties in the experimental values. This confirms our starting premise that vitrinite reflectance is properly described by standard chemical kinetics with activation energies that extrapolate from laboratory to geological maturation temperatures. The model indicates that the relationship between the extent of oil generation and vitrinite reflectance is nearly independent of heating rate.

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A chemical kinetic model of vitrinite maturation and reflectance

Abstract

Geothermics

Geochim. Cosmochim. Acta

Geochim. Cosmochim. Acta

Fuel

Fuel

Org. Geochem.

Org. Geochem.

Org. Geochem.

Analysis of chemical reaction kinetics using a distribution of activation energies and simpler models

Energy & Fuels

Comparison of methods for measuring kerogen pyrolysis rates and fitting kinetic parameters

Energy & Fuels

Pyrolysis of the Argonne premium coals: activation energy distributions and related chemistry

Energy & Fuels

Time-temperature relation in oil genesis

AAPG Bulletin 58

A discussion of methods of physical characterization used for coal

Kinetics of thermal degradation of char-forming plastics from thermogravimetry. Application to a phenolic plastic

J. Polymer Sci.

Reaktionskinetische Untersuchungen zur Kohlenwasserstoffentbinduug aus Steinkohlen bei niedrigen Aufheizgeschwindigkeiten

Ph.D. dissertation

Petroleum Geochemistry and Geology

Reaction sequences under non-isothermal conditions

Fortschritte der Chemischen Forshung

Coal

Properties of polymers: their estimation and correlation with chemical structure

Chemical models of vitrinite reflectance evolution

Geol. Rund.

The determination of paleo-heat flux from vitrinite reflectance data

AAPG Bull.

Evaluation of petroleum generation by hydrous pyrolysis experimentation

Phil. Trans. Roy. Soc. Lon.

Temperature and geologic time as factors in coalification

Izv. Akad. Nauk. SSSR., Ser. Geol.