Industrial procedure for identifying preferential seepage channels of oil and gas reservoirs of clastic rock

Abstract

The invention discloses an industrial procedure for identifying preferential seepage channels of oil and gas reservoirs of clastic rock. The industrial procedure includes steps of 1), dividing n development phases and dividing wells into n groups according to the development phases of well drilling time; 2), dividing data grids of research areas; 3), interpolating permeability parameters of well points of the well groups 1 to obtain permeability planar distribution grids of the development phases 1; 4), sequentially acquiring permeability planar distribution grids R<1>, R<2>, ..., and R<n> of the n development phases by the aid of a method implemented in the step 3); 5), computing a variation coefficient of a permeability value of each grid point by the aid of results obtained in the step 4) so as to obtain variation coefficient grids P; 6), subtracting the R<1> from the R<n>, assigning values of 1 to the grid points with positive difference values and assigning values of -1 to the grid points with negative difference values to obtain grids T; 7), multiplying the grids P by the grids T to obtain grids Q, drawing contour maps of the grids Q, and utilizing regions larger than 0.3 in the contour maps as the preferential seepage channels. The variation coefficients of the permeability values of the grid points change along with change of the development phases. The industrial procedure has the advantage that oilfield water-flooding development and remaining oil prediction can be guided.

Description

technical field [0001] The invention relates to the field of petroleum development geology, and is an industrial process for identifying dominant seepage channels in clastic rock oil and gas reservoirs. Background technique [0002] In the process of oil and gas water injection development, the high porosity and high permeability (or ultra-high permeability) zone formed by long-term water flooding in the reservoir is called the dominant seepage channel. When the reservoir enters the high (ultra-high) water cut period, the role of the dominant seepage channel in the reservoir will appear, especially in the reservoir with high permeability, this phenomenon is more obvious. Due to the heterogeneity of the reservoir plane and the difference in development conditions, the development of the dominant seepage channels in the reservoirs in different areas in the ultra-high water-cut period is very different, and the dominant seepage channels at different levels have different geolog...

AI Technical Summary

Problems solved by technology

[0007] Although domestic and foreign scholars and oil companies have carried out a lot of research and field tests on the dominant seepage channels of reservoirs, and summarized a series of identification methods, d