Effectiveness evaluation method for compact sandstone reservoir map cracking system

Abstract

The invention belongs to the field of oil exploration and particularly relates to an effectiveness evaluation method for a compact sandstone reservoir map cracking system. The effectiveness evaluation method for the compact sandstone reservoir map cracking system includes the following steps that a crack discrete network geologic model is established, crack formation periods are statistically analyzed, crack filling sources are statistically analyzed, crack superior filling directions and systems are statistically analyzed, crack filling master control geologic factors are analyzed, the relation between the crack permeability and current primary stress is established, and the space effectiveness of the map cracking system is evaluated. The purposes of accurately acquiring effective evaluation of compact sandstone reservoir well point crack filling periods, filling superior directions, filling degrees and the space effectiveness of the map cracking system are achieved, the filling degrees and the filling superior directions of compact sandstone reservoir cracks under the multi-period formation fluid precipitation and crystallization effect are effectively predicted, guarantees are provided for fracturing modification design and development scheme optimization of a fractured reservoir, and the risk and cost of exploration and development are reduced.

Description

technical field [0001] The invention belongs to the field of petroleum development, and in particular relates to an evaluation method for the spatial effectiveness of complex network fractures in tight sandstone reservoirs. Background technique [0002] As the exploration and development of oil and gas resources gradually shifts from east to west, and from conventional reservoirs to unconventional reservoirs, searching for fractured oil and gas reservoirs has become a hot spot. How to predict the spatial distribution of fractures and effectively evaluate the space of complex network fracture systems Filling degree or effectiveness is the frontier issue and "bottleneck" issue of oil and gas development research. Compared with other types of reservoirs, tight sandstone reservoirs have a large burial depth, high formation pressure coefficient, strong diagenesis, multiple structural movements, and well-developed network fractures. Structural fractures are important storage space...

AI Technical Summary

Problems solved by technology

Practice has proved that the key factors that determine the effectiveness of the spatial fracture network are the fracture opening and filling degree. For the opening parameter, logging interpretation, core observation and geomechanics methods can be used to predict the difference between wells from point to surface, but filling The parameters are not only directly related to the rock composition, fluid composition and saturation of the reservoir, but also affected and constrained by many factors such as fracture formation stage, formation time, occurrence, mechanical properties, connectivity degree, and structural location, so that the fracture system can be filled There is a strong heterogeneity in the degree, and the method of only using "well point constraint space to make inter-well difference" often runs counter to the mineral dissolution-filling mechanism and achieves the opposite effect, which restricts the geological modeling of complex fracture networks and is beneficial to reservoirs. Layer prediction and development plan optimization process

Images