Response of clastic reservoir to magmatic intrusion: Advances and prospects

Abstract

Exploration practice shows that magmatism-affected clastic reservoirs have potential in oil and gas exploration, but it lacks systematic understanding of the effect of magmatic intrusion on the surrounding clastic rocks. This paper shows that the influence range of magmatic intrusion into clastic reservoirs is positively correlated with the size of magmatic body. The influencing factors mainly include compressive deformation, high temperature, and hydrothermal activity. Magmatic intrusion into clastic reservoirs not only produce physical fractures or dissolve pores, but also lead to mineral precipitation to deteriorate the reservoir space. The vertical and horizontal migration of hydrothermal fluids complicate the distribution of reservoir space and induce reservoir heterogeneity. We further explore: 1) magmatic-hydrothermal information in clastic reservoirs through the analysis of fracture-related veins at different locations in the surrounding reservoirs and, 2) modification effects of magmatic intrusion in clastic reservoirs constrained by geothermometers and anomalous temperature fields. With the guidance of theories and previous studies, we can carry out research using key techniques such as SILLi heat transfer modeling and carbonate U–Pb dating. We aim to develop a comprehensive quantitative model for evaluating the thermal response of clastic reservoirs to magmatic intrusion, and revealing the co-evolution of temperature, thermal convection response and porosity of reservoir modification effect.