Review of Kerogen's Geomechanical Properties: Experiments and Molecular Simulation

Area of Science:

• Geomechanics
• Organic Geochemistry
• Materials Science

Background:

• Kerogen, the primary organic component in shale, possesses significantly lower stiffness than inorganic minerals.
• Its mechanical properties are crucial for understanding shale behavior during processes like hydraulic fracturing.
• Kerogen's mechanical characteristics are influenced by maceral composition and thermal maturity.

Purpose of the Study:

• To comprehensively review experimental methods for determining kerogen's mechanical properties.
• To contrast experimental findings with results from molecular simulations.
• To correlate kerogen's intrinsic attributes (type, maturity) with its measured physical qualities.

Main Methods:

• Experimental characterization of kerogen mechanical properties.
• Molecular simulation of kerogen behavior.
• Comparative analysis of experimental and simulation data.

Main Results:

• Kerogen-rich regions exhibit lower elastic modulus (approx. 10 GPa) compared to minerals like quartz (approx. 70 GPa).
• Kerogen nanocantilever beams demonstrate elastic strain-hardening, requiring more energy for crack propagation.
• Kerogen mechanical properties are positively correlated with maturity and influenced by maceral type.

Conclusions:

• Accurate knowledge of kerogen mechanical properties is vital for optimizing hydraulic fracturing.
• Experimental and simulation approaches provide complementary insights into kerogen's mechanical behavior.
• Understanding kerogen's mechanical response is key to predicting shale reservoir performance.