Carbonate Reservoir Tectonic Fracture Distribution Projections And Quantitative Parameters Field To Form A Preliminary Study

It is more than half of wholly proved reserves is occupied by carbonate reservoirs on the worldwide scale, at the same time it is playing an important role in the oil & gas production of the world. In our country, carbonate reservoirs has distributed widely and owns rather geological reserves. Carbonate reservoirs have strong heterogeneity. Structural fractures and pores make their reservoir space various, complex and difficult to develop. So exactly describing and prediction the structural fracture is the key to exploit carbonate reservoirs in effect. There into how to describe the fracture parameter and predict the fracture quantificationaly in extensity and forming the parameter field is one of the difficult problems.Focused on the relational problems about fracture prediction in the carbonate reservoirs, giving Jialingjiang gas reservoir as an example, using structural main curvature method and applies multidisciplinary techniques, this paper presents a systemic approach, which is suitable for carbonate reservoirs' fracture prediction and calculating three-dimensional quantitative parameter field. This method explores some means and avenue for analogous reservoirs' fracture prediction and forming three-dimensional quantitative parameter field, expands the structural main curvature method's application area. It has biggish difficulty and depth, at the same time has some innovation and breach. Through the theoretical analysis and practice, the achievements of this paper are as follows:(l)Through analyzing the carbonate reservoir characteristics and the fracture generating reasons by the numbers, it points out that tectonic stress field is the dominant factor to control its fracture growth.(2)Inducing and summarizing the fracture prediction methods, according to the carbonate mechanics characteristics and the structural fracture generating reasons, this paper adopts structural main curvature method to predict fracture growth. Appling this method in Jialingjiang gas reservoir, the results confirmed its feasibility.(3) It ascertains the fracture description parameters: fracture length, width, dip, density, interval, fracture porosity and permeability, etc. There into fracture porosity and permeability is the most important but difficult to calculate parameter.(4)Through multivariate statistical analysis, it presents the correlative relation between fracture interval and reservoir thickness and porosity, which is able to predict the interval change in cross-hole area.(5)Based on the geologic research and fracture description, this paper uses structural main curvature method, calculating fracture three-dimensional quantitative porosity and permeability parameter distribution. Example of its application shows that the fracture model giving in this paper can objectively reflect the actual geologic feature.