岩石热物理参数温度依赖性对岩浆侵入体相邻烃源岩热演化重构影响的定量研究

Magma intrusions can change thermal evolution history of organic-rich host rocks, consequently affecting history and potential of hydrocarbon generation of host rocks. Heat transfer models are one of the most important tools for reconstructing thermal evolution history and organic-matter maturity of host rocks. Its accuracy depends on reliable thermo-physical parameters of rocks. Based on the thermo-physical parameters measured at different temperatures, the temperature dependence of thermo-physical parameters was constructed and the deviation in model prediction due to the temperature dependence was quantitatively evaluated by using heat conduction models. Results indicate that: (1) the model considering the temperature dependence of thermo-physical parameters can significantly underestimate the peak temperature of host rocks; (2) ignoring the temperature dependence of the thermo-physical properties will cause the prediction deviation of ~60oC in the contact temperature of magma intrusion; (3) the temperature dependence of the thermo-physical parameters can also cause significant prediction deviation in vitrinite reflectance. Ignoring the temperature dependence will obviously underestimate the degree and extent of thermal effect of magma intrusion on organic-matter maturation.