CN-115166858-B - Gas-water identification method and device for compact water-containing gas reservoir

CN115166858BCN 115166858 BCN115166858 BCN 115166858BCN-115166858-B

Abstract

The method comprises the steps of obtaining a logging curve and reservoir interpretation parameters of a target reservoir gas reservoir, dividing the target reservoir gas reservoir into at least one gas group according to a deposition environment, diagenetic conditions, lithology parameters and physical parameters of the target reservoir gas reservoir, dividing each gas group once according to the electrical parameters, the physical parameters and the gas-containing parameters to obtain a pure gas layer region, a gas layer and gas-water layer mixed region, a pure gas and water layer mixed region and boundaries of each region, and dividing the gas layer and the gas-water layer mixed region secondarily according to the logging curve to obtain the gas layer region and the gas-water layer mixed region and boundaries. The method provided by the invention can obtain accurate limits of different fluid property intervals of the reservoir gas reservoir, is beneficial to improving the calculation reliability of the natural gas reserves, reasonably performing exploration, development and deployment, reducing the gas testing cost and improving the development economy.

Inventors

TIAN LENG
SUN ZHENGYI
ZHANG CHUNYANG
WANG ZECHUAN
WANG JIANGUO
WANG YIPENG
HUANG CAN

Assignees

中国石油大学(北京)
北京众博达石油科技有限公司

Dates

Publication Date: 20260512
Application Date: 20220804

Claims (7)

1. A method for identifying gas and water in a tight gas reservoir, comprising: Acquiring a logging curve of a target reservoir gas reservoir and reservoir interpretation parameters, wherein the reservoir interpretation parameters comprise lithology parameters, electrical parameters, physical parameters and gas-containing parameters; dividing a target reservoir gas reservoir into at least one gas group according to a deposition environment, diagenetic conditions, lithology parameters and physical parameters of the target reservoir gas reservoir; Dividing each gas group once according to the electrical parameter, the physical parameter and the gas-containing parameter to obtain the boundaries of a pure gas layer region, a gas layer and gas-water same layer mixed region, a pure gas-water same layer region and each region; According to the logging curve, performing secondary division on the gas layer and gas-water same-layer mixed region to obtain a gas layer region, a gas-water same-layer region and a boundary; the logging curves of the target reservoir gas reservoir comprise a deep lateral resistivity curve and a shallow lateral resistivity curve; according to the logging curve, performing secondary division on the gas layer and gas-water same-layer mixed region to obtain a gas layer region, a gas-water same-layer region and a boundary, and further comprising: calculating the difference value of the deep lateral resistivity and the shallow lateral resistivity of each gas test sampling point in the gas layer and gas-water same-layer mixed region; drawing a third intersection graph of the difference and the resistivity; according to the third intersection diagram, the air layer and air-water same-layer mixing area is divided for the second time; according to the third intersection diagram, the air layer and air-water same-layer mixing area is divided for the second time, and the method further comprises the following steps: Determining a difference threshold value for dividing the air layer area and the air-water same layer area according to the third intersection diagram; When the difference value of the gas test sampling points is smaller than the difference value threshold value, determining that the gas test sampling points correspond to the gas-water same-layer area; And when the difference value of the gas test sampling points is larger than or equal to the difference value threshold value, determining that the gas test sampling points correspond to the gas layer areas.
2. The method of claim 1, wherein the lithology parameter comprises at least a shale content, the electrical property parameter comprises at least a resistivity, the physical property parameter comprises at least a porosity, and the gas-bearing parameter comprises at least a water saturation.
3. The method of claim 2, wherein dividing each gas group once based on the electrical parameter, the physical parameter, and the gas-containing parameter to obtain a pure gas layer region, a mixed gas layer and gas-water layer region, a pure gas-water layer region, and boundaries of each region, further comprises: Drawing a first intersection chart according to the resistivity, the porosity and the water saturation of each gas group gas test sampling point; And dividing the pure gas layer region, the gas layer and gas-water same layer mixed region, the pure gas-water same layer region and the boundaries of the regions according to the first intersection diagram.
4. The method of claim 1, wherein prior to dividing each gas group once based on the electrical parameter, the physical parameter, and the gas-containing parameter to obtain a pure gas layer region, a gas layer and gas-water co-layer mixed region, a pure gas-water co-layer region, and boundaries of each region, the method further comprises: drawing a second intersection chart according to the resistivity and the argillaceous content of each gas group test gas sampling point; Determining lithology boundaries of each gas group according to the second intersection map; And when the lithology limit is smaller than or equal to a preset value, judging that the gas group has development value and executing a primary dividing step of the gas group.
5. A compact aqueous gas reservoir gas-water identification apparatus comprising: The system comprises an acquisition module, a control module and a control module, wherein the acquisition module is used for acquiring a logging curve of a target reservoir gas reservoir and reservoir interpretation parameters, and the reservoir interpretation parameters comprise lithology parameters, electrical parameters, physical parameters and gas-containing parameters; the gas group dividing module is used for dividing the target reservoir gas reservoir into at least one gas group according to the deposition environment, the diagenetic condition, the lithology parameter and the physical property parameter of the target reservoir gas reservoir; The primary dividing module is used for dividing each gas group once according to the electrical parameters, the physical parameters and the gas-containing parameters to obtain boundaries of a pure gas layer region, a gas layer and gas-water same layer mixed region, a pure gas-water same layer region and each region; the secondary division module is used for carrying out secondary division on the gas layer and gas-water same-layer mixed region according to the logging curve to obtain a gas layer region and a gas-water same-layer region and a boundary; the secondary partitioning module is further configured to measure a well log of the target reservoir gas reservoir, where the well log includes a deep lateral resistivity curve and a shallow lateral resistivity curve; according to the logging curve, performing secondary division on the gas layer and gas-water same-layer mixed region to obtain a gas layer region, a gas-water same-layer region and a boundary, and further comprising: calculating the difference value of the deep lateral resistivity and the shallow lateral resistivity of each gas test sampling point in the gas layer and gas-water same-layer mixed region; drawing a third intersection graph of the difference and the resistivity; according to the third intersection diagram, the air layer and air-water same-layer mixing area is divided for the second time; according to the third intersection diagram, the air layer and air-water same-layer mixing area is divided for the second time, and the method further comprises the following steps: Determining a difference threshold value for dividing the air layer area and the air-water same layer area according to the third intersection diagram; When the difference value of the gas test sampling points is smaller than the difference value threshold value, determining that the gas test sampling points correspond to the gas-water same-layer area; And when the difference value of the gas test sampling points is larger than or equal to the difference value threshold value, determining that the gas test sampling points correspond to the gas layer areas.
6. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the method of any one of claims 1 to 4 when the computer program is executed.
7. A computer readable storage medium, characterized in that the computer readable storage medium stores a computer program which, when executed by a processor, implements the method according to any one of claims 1 to 4.

Description

Gas-water identification method and device for compact water-containing gas reservoir Technical Field The invention relates to the technical field of oil and gas exploration and development, in particular to a method and a device for identifying gas and water in a compact water-containing gas reservoir. Background The exploration and development of the compact water-containing gas reservoir have the advantages of poor physical properties of the reservoir, strong non-average property in and between layers, undeveloped hydrocarbon source rock and limited resource quantity, so that partial gas reservoir is unsaturated in the natural gas filling process, and the defect of uniform gas-water interface is avoided, thereby the influence of rock frameworks in most reservoirs on the resistivity is far higher than that of fluid. The response characteristics of acoustic wave time difference, density and compensation neutron curve are also skeleton information, but are not sensitive to fluid, so that the common phenomenon of high-resistance gas-water output and low-resistance pure gas production is high in gas-water identification difficulty. In recent years, with the continuous deep research on reservoir fluid identification, experimental methods and means are continuously perfected, and a plurality of research results are obtained. However, from the current state of research at home and abroad, a method system capable of comprehensively solving the problem of gas and water identification in a water-containing gas reservoir with complex gas-water relationship is lacking, and in a compact water-containing gas reservoir, gas-water identification and evaluation technology research is still in an exploration stage. In view of the above, it is an object herein to provide a method and apparatus for gas-water identification of tight gas reservoirs. Disclosure of Invention Aiming at the problems in the prior art, the object of the present invention is to provide a dense water-containing gas reservoir gas-water identification method and device, so as to solve the problem of accuracy in gas and water identification in the water-containing gas reservoir in the prior art and provide reliable support basis for gas field exploration and development. In order to solve the technical problems, the specific technical scheme is as follows: In a first aspect, provided herein is a method of gas-water identification of a tight aqueous gas reservoir, comprising: Acquiring a logging curve of a target reservoir gas reservoir and reservoir interpretation parameters, wherein the reservoir interpretation parameters comprise lithology parameters, electrical parameters, physical parameters and gas-containing parameters; dividing a target reservoir gas reservoir into at least one gas group according to a deposition environment, diagenetic conditions, lithology parameters and physical parameters of the target reservoir gas reservoir; Dividing each gas group once according to the electrical parameter, the physical parameter and the gas-containing parameter to obtain the boundaries of a pure gas layer region, a gas layer and gas-water same layer mixed region, a pure gas-water same layer region and each region; And carrying out secondary division on the gas layer and gas-water same layer mixing zone according to the logging curve to obtain a gas layer zone, a gas-water same layer zone and a boundary. Preferably, the lithology parameter comprises at least a shale content, the electrical parameter comprises at least a resistivity, the physical property parameter comprises at least a porosity, and the gas-bearing parameter comprises at least a water saturation. Further, according to the electrical parameter, the physical parameter and the gas-containing parameter, dividing each gas group once to obtain a pure gas layer region, a mixed region of a gas layer and a gas-water layer, a pure gas-water layer region and boundaries of each region, including: Drawing a first intersection chart according to the resistivity, the porosity and the water saturation of each gas group gas test sampling point; And dividing the pure gas layer region, the gas layer and gas-water same layer mixed region, the pure gas-water same layer region and the boundaries of the regions according to the first intersection diagram. Preferably, before dividing each gas group once according to the electrical parameter, the physical parameter and the gas-containing parameter to obtain a pure gas layer region, a gas layer and gas-water same layer mixed region, a pure gas-water same layer region and boundaries of each region, the method further comprises: drawing a second intersection chart according to the resistivity and the argillaceous content of each gas group test gas sampling point; Determining lithology boundaries of each gas group according to the second intersection map; And when the lithology limit is smaller than or equal to a preset value, judging that the gas group has development