Thermal Maturation-Induced Variation of P-wave Anisotropy and Dry Resistivity of Organic-Rich Shale

The main purpose of this study is to establish the cause-and-effect relationships between geochemical parameters and microstructure/rock physics as organic-rich shales mature. By iteratively studying samples upon pyrolysis, we avoid auxiliary effects, e.g., mineralogical variations, and characterize sample evolution solely as a function of thermal maturation. P-wave anisotropy and pressure-sensitivity data coupled with time-lapse, high-resolution BSE-SEM images indicate significant development of soft porosity, e.g., micro-cracks, post-pyrolysis to the wet-gas window. Additionally, dry resistivity measurements indicate an average 82% decrease in shale resistivity upon thermal maturation to the wet-gas window.