Matrix permeability calculation method and system

Abstract

The invention discloses a matrix permeability calculation method and system. The method comprises the following steps of establishing natural gamma neutron logging cross plots of sandstones with different granularities, and determining constraint boundaries of the sandstones with different granularities; obtaining a rock granularity profile according to the natural gamma neutron logging cross plot; determining granularity median ranges corresponding to different granularities according to the rock granularity profile; establishing a cross plot according to the known particle size median, the constraint boundary and the natural gamma, and calculating the initial particle size median of the unknown sandstone; determining the particle size median of the unknown sandstone according to the particle size median range corresponding to the unknown sandstone and the initial particle size median; and calculating permeability of the matrix according to the particle size median. According to the method, evaluation of the matrix permeability is realized by establishing the granularity profile calculation chart and calculating the granularity median, the influence of granularity on the matrix permeability is reflected, and permeability of the double-hole medium reservoir can be accurately determined by combining the fracture permeability.

Description

technical field

[0001] The invention relates to the field of petroleum exploration and development, and more specifically, to a method and system for calculating matrix permeability. Background technique

[0002] Permeability is an important parameter to measure the permeability of reservoirs, and plays a very important role in the exploration and development of oil and gas fields. To evaluate permeability by logging, the indirect evaluation of permeability is mostly achieved by establishing its relationship with other petrophysical parameters. For single-porous media, the pore space is mainly primary intergranular pores, and the homogeneity is good. The earliest research on single-porosity sandstone found that the logarithm of permeability has a linear relationship with porosity. However, this method does not consider the influence of pore structure changes, and cannot meet the accuracy requirements of complex reservoir permeability evaluation. Subsequently, the relationsh...

Examples

Embodiment Construction

[0039] The present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0040] figure 1 A flowchart showing the steps of the matrix permeability calculation method according to the present invention.

[0041] In this embodiment, the method for calculating matrix permeability according to the present invention may include: step 101, establishing a natural gamma-neutron logging crossplot of sandstones with different particle sizes, and determining the constraint limits of sandstones with different particle sizes; step 102, according to natural Gamma-neutro...

technical field

[0001] The invention relates to the field of petroleum exploration and development, and more specifically, to a method and system for calculating matrix permeability. Background technique

[0002] Permeability is an important parameter to measure the permeability of reservoirs, and plays a very important role in the exploration and development of oil and gas fields. To evaluate permeability by logging, the indirect evaluation of permeability is mostly achieved by establishing its relationship with other petrophysical parameters. For single-porous media, the pore space is mainly primary intergranular pores, and the homogeneity is good. The earliest research on single-porosity sandstone found that the logarithm of permeability has a linear relationship with porosity. However, this method does not consider the influence of pore structure changes, and cannot meet the accuracy requirements of complex reservoir permeability evaluation. Subsequently, the relationsh...

Examples

Embodiment Construction

[0039] The present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0040] figure 1 A flowchart showing the steps of the matrix permeability calculation method according to the present invention.

[0041] In this embodiment, the method for calculating matrix permeability according to the present invention may include: step 101, establishing a natural gamma-neutron logging crossplot of sandstones with different particle sizes, and determining the constraint limits of sandstones with different particle sizes; step 102, according to natural Gamma-neutro...

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