Method and apparatus for determining permeability of reservoir

Patent metadata

Field	Value
Publication number	US-11086034-B2
Application number	US-201816159052-A
Country	US
Kind code	B2
Filing date	Oct 12, 2018
Priority date	Aug 15, 2017
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

The embodiments of the present disclosure disclose a method and an apparatus for determining the permeability of the reservoir. The method comprises: acquiring logging data corresponding to the two zones at least; determining the permeability of a specified zone in the two zones at least based on logging data corresponding to the specified zone, wherein the specified zone represents any one of the two zones at least; setting weight values corresponding to the at least two zones respectively; and determining the permeability of the reservoir based on the weight values and the permeability respectively corresponding to the two zones at least. The technical solutions provided by the embodiments of the present disclosure can improve the accuracy of the determined permeability of the reservoir.

First claim

The invention claimed is:

1. A method for determining the permeability of a reservoir, wherein the reservoir comprises at least two borehole radial zones, each of the zones comprises annular regions centered on a well axis of a target well in the reservoir, and the annular regions are located outside the target well, wherein the at least two borehole radial zones comprised in the reservoir are a first zone, a second zone, a third zone, and a fourth zone respectively; wherein a distance between the first zone and a target borehole ranges from 0 m to 0.1 m, a distance between the second zone and the target borehole ranges from 0.1 m to 1 m, a distance between the third zone and the target borehole ranges from 1 m to 10 m, and a distance between the fourth zone and the target borehole ranges from 10 m to 40 m; the method comprises:
acquiring logging data corresponding to the at least two zones respectively;
determining the permeability of a specified zone in the at least two zones based on logging data corresponding to the specified zone, wherein the specified zone represents any one of the at least two zones;
setting weight values corresponding to the at least two zones respectively; and
determining the permeability of the reservoir based on the weight values and the permeability respectively corresponding to the at least two zones,
wherein,
logging data corresponding to the first zone comprises an electrically imaged logging image;
logging data corresponding to the second zone comprises array acoustic wave logging data;
logging data corresponding to the third zone comprises monopole far-detection logging data; and
logging data corresponding to the fourth zone comprises dipole far-detection logging data;
correspondingly,
determining the permeability of the first zone based on the electrically imaged logging image;
determining the permeability of the second zone based on the array acoustic wave logging data;
determining the permeability of the third zone based on the monopole far-detection logging data; and
determining the permeability of the fourth zone based on the dipole far-detection logging data,
wherein determining the permeability of the first zone based on the electrically imaged logging image comprises:
calculating a porosity of a specified pixel point in the electrically imaged logging image in the following formula:

ϕ
i

=

a
·
b
·

R
mf

·

C
i

m

wherein, ϕ i represents a porosity of an i-th pixel point in the electrically imaged logging image; a and b represent lithology factors respectively; m represents a formation cementation index; R inf represents a mud filtrate resistivity; and C i represents a conductivity of the i-th pixel point in the electrically imaged logging image;
determining a porosity distribution spectrum according to the porosity of the specified pixel point;
dividing the porosity distribution spectrum into a matrix porosity distribution spectrum and a secondary porosity distribution spectrum according to a preset porosity spectrum cutoff value, thereby obtaining a matrix porosity corresponding to the matrix porosity distribution spectrum and a secondary porosity corresponding to the secondary porosity distribution spectrum;
calculating the permeability of the first zone based on the matrix porosity and the secondary porosity in the following formula:
K 1 =f 1 10 ka1×φ matric +kb1 +f 2 10 ka2×φ fv kb2

wherein, K 1 represents the permeability of the first zone; f 1 and f 2 represent a matrix permeability coefficient and a secondary pore permeability coefficient respectively; ka1 and ka2 represent porosity indexes respectively; kb1 and kb2 represent permeability constants respectively; and φ matrix and φ fv represent the matrix porosity and the secondary porosity respectively.

2. The method for determining the permeability of a reservoir according to claim 1 , wherein determining the permeability of the second zone based on the array acoustic wave logging data comprises:
determining Stoneley wave information corresponding to the second zone based on the array acoustic wave logging data, wherein the Stoneley wave information comprises at least one of a Stoneley wave attenuation rate and a Stoneley wave velocity;
calculating the permeability of the second zone based on the Stoneley wave information in the following formula:

k
=

k
e
2

+

2
⁢

⁢
i
⁢

⁢

ρ
pf

⁢
ω
⁢

⁢

K
2

⁢
R

η
⁡

(

R
2

-

r
2

)

⁢

-
i

⁢

⁢

ω
/
D

+

k
e
2

⁢

A
1

⁡

(

R
⁢

Assignees

• Petrochina Co Ltd

Inventors

• Li Ning
• Wu Hongliang
• Feng Zhou
• Liu Peng
• Wang Kewen
• Feng Qingfu
• Li Yusheng

Classifications

• G01V3/20

  operating with propagation of electric current · CPC title

• G01V11/00 Primary

  Prospecting or detecting by methods combining techniques covered by two or more of main groups G01V1/00 - G01V9/00 · CPC title

• G01V1/306 Primary

  for determining physical properties of the subsurface, e.g. impedance, porosity or attenuation profiles · CPC title

• G01V2210/6244

  Porosity · CPC title

• G01V3/38

  Processing data, e.g. for analysis, for interpretation, for correction · CPC title