Abstract:

 Based on the data of directional core drilling, FMI, routine cores and their thinsections, we have described the characteristics of H3 reservoir in Anpeng oil field, Miyang sag. By analyzing the stable isotopes of 20 fracture infillings and 5 groups of acoustic emission, combined with the studies of fracture characteristics and tectonic evolution, the fractures in H3 member were assigned to the regional fracture type which is characterized by the dominance of vertical or highangle extensional fracture, occurring in groups, relatively stable occurrences and out of the control of local nosetype folds. It has been recognized that there are 4 breaking stages, of which the 2nd one is the major stage. Based on the rock mechanical properties, the distribution of rigid rocks, the thickness of sandstones and the intensity of tectonic stress field, we have systematically discussed the geological factors controlling the fracture developments. The regional stress intensity closely related to the degree of the fracture development is the major extrinsic factor influencing the fractures, while the lithology, the density and the thickness of rocks are the major intrinsic causes. The procedures of tectonic filtering, the stress field simulation and the main curvature calculation have been employed to anticipate and evaluate the areal distribution of fractures of the reservoir groups of Ⅶ, Ⅷ and Ⅸ in the study area.

Key words:

Key words: Miyang sag; Anpeng oil field; causes of fractures; fracture stages; distribution of fractures