COMPENSATION EFFECT IN SOURCE ROCK KINETICS: INFLUENCE OF BITUMEN FORMATION
To simulate thermal maturation (immature, early mature, and late mature) periods, a series of artificial maturation processes on Bakken Shale was carried out. Firstly, we performed source rock analysis to estimate the thermal maturity of the study samples. Second, we applied the principle of Arrhenius Equation and Kissinger Equation in the kinetic analysis to derive Ea and ln(A). Photomicrographs of the research samples were collected to assess the observation made by the microscope that fluorescent kerogen disappears as thermal maturation progresses. Finally, the artificially matured samples were cleaned using the dean stark extraction method to remove bitumen and we repeated the methods cited above.
Results show that geochemical properties such as the total organic carbon changed with increasing thermal maturity. The kinetic analysis reveals that Ea and ln(A) have a second, strongly correlated, and linear compensation effect. This demonstrates that, rather than the statistical compensation predicted by the linear trends in the experimental kinetic, there is a residual compensation effect that may have a physiochemical basis. Ignoring this residual compensation effect will lead to reaction rate error