Study On Reservoir Characteristics Of Paleogene Igneous Rock In Shang 741 Area Of Huimin Depression

Domestic and international exploration indicates that igneous rock can be a good reservoir, and more and more igneous reservoirs were found. Typical igneous reservoirs develop in Paleogene of Shang 741 area of Huimin Depression. Because of its complex storage space types and its unevenly distribution, the exploration and development of the igneous reservoirs are not good. In this thesis, reservoir characteristics of igneous rock in Shahejie formation, Paleogene in Shang 741 area is systematically studied with drilling geological data, logging and seismic data.This study shows that three types of igneous rocks, including volcaniclastic rock, basalt and dolerite, develop in Paleogene of Shang 741 area, Huimin Depression. Their characteristics on conventional log and FMI are different. On seismic section, the reflection configuration of igneous rocks presents like "mushrooms", "dome shape", "plate" and so on. Their internal reflection is not obvious or like a messy "moundy shape", "imbricate arrangement shape" or "vermiform". The igneous rocks distributed mostly nearby faults. Volcanic cones developed in Es1 formation with limited distribution while intrusive rocks developed widely in Es3z. Hydrocarbon has been discovered in volcanic cone, which developed in Shang 74-6 well block in Es1 formation, and intrusive rock, which developed in Es3z. Volcanic cone in Shang 74-6 well block can be generally classified into four subfacies including crater,near crater distal crater subfacies and volcanic sedimentary subfacies. Different phase belts show ring ribbon distribution. From inside to outside, intrusive lithofacies can be classified as central subfacies, transitional subfacies and edge subfacies. The combinatorial model of every subfacies belt is spatially symmetric. Storage space types of igneous rocks are mainly pore (or cave) and fracture. The main storage space type of volcanic cone is fracture-pore (or cave) while that of intrusive rock is fracture. Development of igneous reservoir is mainly controlled by lithofacies, lithology, tectonic activities and so on. Considering the lithofacies, storage space and its development degree and physical properties, volcanic cone reservoir in Es1 member is classified as two types: classâ… reservoir is the pore development area, which located in the crater subfacies and near crater subfacies, and fracture development area, which located near the faults. Classâ…¡reservoir is the volcaniclastic rock in distal crater subfacies and volcanic sedimentary subfacies. Intrusive rocks of Es3z member is divided into three types: classâ… reservoir developed in the fracture development zone which mainly located in central subfacies; classâ…¡reservoir mainly developed in the fracture development zone which located in the edge and transition subfacies; the intrusive rocks, in which fracture and pore hardly developed, is classâ…¢reservoir.