CN118148608A - Method, system and equipment for discriminating fluid in tight gas reservoir - Google Patents

Abstract

The invention discloses a method, a system and equipment for discriminating a tight gas reservoir fluid, and belongs to the technical field of tight gas exploration and development. The distinguishing method comprises the following steps: acquiring logging data and logging data, and preprocessing to obtain standardized data; analyzing the parameter sensitivity through single parameter intersection based on the standardized data, and creating a composite parameter; the method comprises the steps of determining the sensitivity of composite parameters and single parameters to gas and water, and selecting the sensitivity parameters to establish a three-dimensional drawing, wherein the discrimination method solves the problems of single compact gas reservoir fluid interpretation method, low pertinence, low compact gas interpretation coincidence rate and low gas testing success rate.

Description

Method, system and equipment for discriminating fluid in tight gas reservoir

Technical Field

The invention belongs to the technical field of dense gas exploration and development, and particularly relates to a dense gas reservoir fluid discrimination method, a system and equipment thereof.

Background

The tight gas reservoir has the characteristics of strong reservoir heterogeneity, low pore size, low permeability, gas-water differential and the like, and in the exploration and development process of tight gas, the tight gas reservoir fluid evaluation is generally carried out by adopting a single logging parameter intersection method, an induction-lateral joint measurement method, an envelope surface method, a nuclear magnetic logging interpretation method and other gas hydrolysis release technologies. The single logging parameter intersection method is to establish different interpretation plate patterns for the intersection of nine conventional logging curves (GR, SP, CAL, AC, DEN, CNL, RD, RS, RXO), and the common intersection plate comprises an acoustic resistivity intersection method, a resistivity ratio method, a porosity difference method and the like. The induction-lateral joint measurement method is to establish deep induction and deep lateral joint measurement parameters according to an array induction parallel principle and a lateral logging series principle, establish a cross plate and develop reservoir fluid discrimination. The envelope surface method is to build different envelope surface intersection plates according to the gas-containing characteristics of the reservoir, the acoustic wave time difference, the resistivity increase, the density and the neutron decrease, and the mining effect or the envelope phenomenon. According to different relaxation times of gas and water, the nuclear magnetic resonance well logging interpretation method adopts a proper measurement mode to highlight the difference between the gas and the water, and adopts a shift spectrometry and a difference spectrometry to carry out gas and water identification.

The prior art has the following disadvantages:

(1) The existing interpretation method has low coincidence rate. The single logging parameter method is mainly aimed at a conventional high-hole hypertonic reservoir. The method has poor practicability for the unconventional gas reservoir of the tight sandstone, and the gas-water layer of the low-pore hypotonic reservoir has no obvious logging response difference. Because the permeability of a tight sandstone gas reservoir is poor, the longitudinal and transverse heterogeneity of the reservoir is strong, the reservoir mainly comprises capillary Kong Weixiao holes, the gas-water coexistence phenomenon is common, and the like, the gas content of the reservoir is influenced by the natural gas filling strength, the lithology, physical properties and other factors of the reservoir, comprehensive analysis influence factors are required to be considered during gas hydrolysis release, and the interpretation precision is improved.

(2) Under the influence of factors such as bound water, microcracks and the like, the low-gas-resistance layer in the development part of the reservoir is better in application of an induction-lateral joint measurement method in the low-gas-resistance layer, array induction is applicable to a low-resistance high-mineralization bottom layer, but a tight sandstone gas reservoir is influenced by an original stratum, the distribution range of the mineralization degree of stratum water is wider, and the difference of the accuracy of the array induction in the high-resistance stratum and the low-resistance stratum is larger; the response characteristics of the gas-water layer are affected, the effect of the envelope surface method on explaining the producing layer and the non-producing layer is better, the effect of finely explaining the fluid types such as the gas-water same layer, the gas-water layer, the gas-difference layer and the like is poorer, and the determination limitation of quantitative parameters is larger.

(3) Nuclear magnetic logging is expensive to interpret, cannot be widely used, and has no popularization.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a dense gas reservoir fluid discrimination method, a system and equipment thereof, and the method solves the problems of single dense gas reservoir fluid interpretation method, low pertinence, low dense gas interpretation coincidence rate and low gas test success rate.

In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:

The invention provides a fluid discrimination method for a tight gas reservoir, which comprises the following steps:

s1: acquiring logging data and logging data, and preprocessing to obtain standardized data;

S2: analyzing the parameter sensitivity through single parameter intersection based on the standardized data, and creating a composite parameter;

s3: and determining the sensitivity degree of the single parameter and the composite parameter to the air and the water, selecting the sensitivity parameter to establish a three-dimensional drawing plate, and judging.

In the step S1, the preprocessing is to perform normalization processing on parameter curves with different periods and different scales by a normalization method, so that the data of the parameter curves show determined response characteristics under the same geological condition.

In the step S2, the process of analyzing the parameter sensitivity through single parameter intersection and creating the composite parameter is as follows: based on the gas test data, the well logging data and the logging data, qualitatively analyzing the basic characteristics of a gas-water layer, and semi-quantitatively analyzing single parameters by using a conventional intersection plate method to obtain sensitive parameters; and combining different sensitive parameters, creating a composite parameter containing a plurality of sensitive parameter information, and carrying out pairwise intersection analysis.

In the step S3, the process of determining the sensitivity degree of the composite parameter and the single parameter to the air and the water is as follows: and analyzing the sensitivity of the logging acoustic time difference AC, the stratum true resistivity RT, the density DEN, the logging total hydrocarbon QT, the porosity difference value SACQT comprehensive indexes, the acoustic time difference-compensating neutron AC-CNL envelope surface, the XQT gas-containing index and the POZ water-containing index by utilizing a radar chart to obtain the sensitivity interference factors of composite parameters and single parameters on gas and water, comparing to obtain sensitive parameters, and selecting the sensitive parameters to establish a three-dimensional chart.

The invention further provides that the composite parameters comprise SACQT comprehensive indexes, an AC-CNL envelope surface, XQT gas-containing indexes and POZ water-containing indexes.

The invention further provides the following calculation of SACQT comprehensive indexes:

comprehensive index:

the XQT gas index was calculated as follows:

XQT gas index:

the POZ water index is calculated as follows:

POZ water index: poz=f (Porw, SH, CNL, SW)

Wherein QT is logging whole hydrocarbon; AC is the logging acoustic time difference; is normalized whole hydrocarbon; QT _min is the full hydrocarbon value; /(I) The normalized acoustic wave time difference; AC _min is the acoustic time difference base; h is the thickness of the intersection surface; h _QT is the gas measurement filling thickness; h _GR is sandstone thickness; porw is the aqueous porosity; SH is the clay content; CNL is compensation neutron; SW is water saturation.

The three-dimensional plate is characterized in that SACQT comprehensive indexes are taken as an abscissa, XQT gas-containing indexes are taken as an ordinate, and POZ water-containing indexes are taken as an ordinate.

The invention further provides that the method further comprises verification of a three-dimensional interpretation technology; the verification process is as follows: and (3) performing a return judgment on the established three-dimensional drawing plate to obtain a three-dimensional interpretation coincidence rate, comparing the two-dimensional single parameter coincidence rate, and verifying by using a new well.

The invention also provides a fluid discrimination system for a tight gas reservoir, which comprises:

The data acquisition processing module is used for acquiring logging data and preprocessing the logging data to obtain standardized data;

the analysis module is used for analyzing the parameter sensitivity through single parameter intersection based on the standardized data and creating composite parameters;

and selecting and establishing a three-dimensional plate module, which is used for determining the sensitivity degree of single parameters and composite parameters to air and water, selecting the sensitive parameters, establishing a three-dimensional plate and judging.

An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing the steps of any of the tight gas reservoir fluid discrimination methods when the computer program is executed.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a discrimination method for a tight gas reservoir fluid, which adopts visual expression form to establish evaluation indexes, and based on single logging parameters and logging parameters, the method finely analyzes the response characteristics of each parameter in the reservoir fluid, analyzes the fusion principle of each parameter and creates favorable conditions for creating a composite index containing more fluid information. Finally, the composite parameters are obtained through mathematical statistics and combination calculation. And intersecting every two of the longitudinal and transverse coordinates, and analyzing the reliability and accuracy of each index. And finally, three indexes are utilized to establish a three-dimensional interpretation plate, so that the three-dimensional interpretation plate has good practical value, and the fluid interpretation coincidence rate is effectively improved.

The judging method can perform gas-water interpretation with high coincidence rate under the condition of no special logging data, and utilizes the existing conventional logging data and gas logging data to provide a gas-water three-dimensional space interpretation technology, so that the comprehensive interpretation coincidence rate of a gas-water layer reaches more than 0.9, the gas hydrolysis release coincidence rate is greatly improved, and technical support is provided for gas testing layer optimization and regional exploration and development.

Drawings

FIG. 1 is a flow chart of a method for explaining the three-dimensional space of a tight gas reservoir according to the present invention;

FIG. 2 is a graph of the creation of the complex index SACQT, aqueous index POZ parameters of the present invention;

FIG. 3 is a graph of the creation of a POZ parameter for the air index XQT and water index of the present invention;

FIG. 4 is a graph of the present invention showing the creation of a parameter intersection of QT-AC envelope (Complex index) and XQT gas-containing index, and FIG. B showing the POZ water-containing index and XQT gas-containing index;

FIG. 5 is a three-dimensional interpretation of a tight gas reservoir of the present invention;

FIG. 6 is a verification diagram of an embodiment of the present invention.

Detailed Description

So that those skilled in the art can appreciate the features and effects of the present invention, a general description and definition of the terms and expressions set forth in the specification and claims follows. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, and in the event of a conflict, the present specification shall control.

The theory or mechanism described and disclosed herein, whether right or wrong, is not meant to limit the scope of the invention in any way, i.e., the present disclosure may be practiced without limitation to any particular theory or mechanism.

All features such as values, amounts, and concentrations that are defined herein in the numerical or percent ranges are for brevity and convenience only. Accordingly, the description of a numerical range or percentage range should be considered to cover and specifically disclose all possible sub-ranges and individual values (including integers and fractions) within the range.

In this context, not all possible combinations of the individual technical features in the individual embodiments or examples are described in order to simplify the description. Accordingly, as long as there is no contradiction between the combinations of these technical features, any combination of the technical features in the respective embodiments or examples is possible, and all possible combinations should be considered as being within the scope of the present specification.

The invention provides a method, a system and equipment for discriminating fluid in a tight gas reservoir.

The invention will be further illustrated with reference to specific examples. It is to be understood that these examples are illustrative of the present invention and are not intended to limit the scope of the present invention.

A method for discriminating a tight gas reservoir fluid, comprising the steps of:

The first step: and (3) processing basic data, carrying out standardized processing on a logging curve, eliminating errors among different logging equipment data at different times, unifying scales, and tamping the basic data.

The regional exploration and development period is long, so that the precision of logging equipment and logging equipment used for exploratory wells in different periods is high, and the scale difference is large, so that a standard well needs to be comprehensively optimized, GR, logging acoustic time difference AC, density DEN and compensation neutron CNL curves in different periods and different scales are preprocessed through a standardized method, and curve data show accurate response characteristics under the same geological condition.

And a second step of: and (3) taking the gas test data as a standard, analyzing the typical gas-water layer logging characteristics, analyzing the parameter sensitivity by utilizing single parameter intersection, and creating composite parameters.

Analyzing the gas test data, determining the reliability of the data, combining the logging data, qualitatively analyzing the basic characteristics of a gas-water layer, grasping the basic geological characteristics, semi-quantitatively analyzing the characteristics and the limit of single logging acoustic time difference AC, stratum true resistivity RT, density DEN, logging total hydrocarbon QT and other parameters in the gas-water layer by using a conventional intersection plate method, and analyzing the fluid information and the limitation of each parameter. Different sensitive parameters are combined to create parameters conforming to a plurality of parameter information, namely a QT-AC envelope surface (comprehensive index), an AC-CNL envelope surface, a XQT gas-containing index and a POZ water-containing index, and the accuracy and the reliability of the parameters are analyzed by intersection.

The composite parameters created: the comprehensive index, XQT gas index, POZ water index were calculated as follows:

comprehensive index:

Gas index:

Water index: poz=f (Porw, SH, CNL, SW)

Wherein SACQT is the comprehensive index; XQT is the gas index; POZ is the water index; QT is logging whole hydrocarbon; AC is the logging acoustic time difference; normalized whole hydrocarbon; QT _min is the full hydrocarbon value; /(I) Normalized acoustic wave time difference; AC _min acoustic time difference base; h is the thickness of the intersection surface; h _QT is the gas measurement filling thickness; h _GR is sandstone thickness; porw is the aqueous porosity; SH is the clay content; CNL is compensation neutron; SW is water saturation.

And a third step of: and comprehensively analyzing the multiple composite parameters and the single parameters to determine the sensitivity degree of each parameter to air and water, and finally, preferably selecting three sensitive parameters as basic data for building the three-dimensional drawing.

The sensitivity of the acoustic wave time difference-compensated neutron AC-CNL envelope surface, XQT gas-containing index and POZ water-containing index is analyzed by utilizing a radar chart, and the results show that the sensitivity interference factors of the QT-AC envelope surface (comprehensive index), the gas-containing index and the water-containing index to gas and water are less, the fluid-containing information is more abundant, and the gas-water identification can be more accurately carried out.

Fourth step: and (5) establishing and verifying a three-dimensional interpretation technology.

And a three-dimensional interpretation chart is established by taking the comprehensive index (AC-QT) as an abscissa, the gas-containing index (XQT) as an ordinate and the water-containing index (POZ) as a Z coordinate, and is subjected to back judgment, wherein the three-dimensional interpretation coincidence rate is 92.2 percent, and the three-dimensional interpretation coincidence rate is 67 percent compared with the two-dimensional single parameter coincidence rate, so that the whole is improved by 22.2 percent. And verified with the new well.

The invention provides a fluid discrimination system for a tight gas reservoir, which comprises the following components:

The data acquisition processing module is used for acquiring logging data and preprocessing the logging data to obtain standardized data;

the analysis module is used for analyzing the parameter sensitivity through single parameter intersection based on the standardized data and creating composite parameters;

and selecting and establishing a three-dimensional plate module, which is used for determining the sensitivity degree of single parameters and composite parameters to air and water, selecting the sensitive parameters, establishing a three-dimensional plate and judging.

The invention provides an electronic device comprising a memory, a processor and a computer program stored in the memory and operable on the processor, wherein the processor implements the steps of any one of the tight gas reservoir fluid discrimination methods when executing the computer program.

The present invention provides a computer readable storage medium storing a computer program which, when executed by a processor, implements the steps of any of the tight gas reservoir fluid discrimination methods.

Example 1

The three-dimensional space interpretation method of the well 3948.8-3954.0m well section reservoir comprises the following steps:

(1) Taking the well depth 3948.8-3954.0m logging data, wherein AC= 232.78 mu s/m; cnl=6.9%; PORW = 2.69%; sw=43.8%; qt=5.54%; QTmin = 0.1825%; hqt=5m; hgr=6m;

(2) Comprehensive index:

(3) Gas index:

(4) Water index: poz=f (Porw, SH, CNL, SW) = -1.21

Example 2

The three-dimensional space interpretation method of the Chu Cengliu body of the well 3972.7-3978.5m well section comprises the following steps:

(1) Taking the well depth 3948.8-3954.0m logging data, wherein AC= 228.02 mu s/m; cnl=5.7%; PORW = 3.09%; sw=38.9%; qt=6.6%; QTmin = 0.125%; hqt=5.5 m; hgr=6.5 m;

(2) Comprehensive index:

(3) Gas index:

(4) Water index: poz=f (Porw, SH, CNL, SW) = -1.34

Example 3

The three-dimensional space interpretation method of the Chu Cengliu body of the well 3989.6-4000.7m well section comprises the following steps:

(1) Taking the well depth 3948.8-3954.0m logging data, wherein AC= 230.9 mu s/m; cnl=6.1%; PORW = 3.34%; sw=33.6%; qt=31.5%; QTmin = 0.064%; hqt=10.5 m; hgr=16.5m;

(2) Comprehensive index:

(3) Gas index:

(4) Water index: poz=f (Porw, SH, CNL, SW) = -1.65

The invention adopts visual expression form to establish evaluation index, based on single logging parameter, the response characteristic of each parameter in reservoir fluid is analyzed finely, and the fusion principle of each parameter is analyzed, thereby creating favorable condition for creating comprehensive index containing more fluid information. And finally, obtaining the comprehensive index, the water content index and the gas content index through mathematical statistics and combination calculation. And intersecting every two of the longitudinal and transverse coordinates, and analyzing the reliability and accuracy of each index. And finally, three indexes are utilized to establish a three-dimensional interpretation plate, so that the three-dimensional interpretation plate has good practical value, and the fluid interpretation coincidence rate is effectively improved.

It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Finally, it should be noted that: the above embodiments are only for illustrating the technical aspects of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those of ordinary skill in the art that: modifications and equivalents may be made to the specific embodiments of the invention without departing from the spirit and scope of the invention, which is intended to be covered by the claims.

Claims (10)

1. A method for discriminating a tight gas reservoir fluid, comprising the steps of:

s1: acquiring logging data and logging data, and preprocessing to obtain standardized data;

S2: analyzing the parameter sensitivity through single parameter intersection based on the standardized data, and creating a composite parameter;

s3: and determining the sensitivity degree of the single parameter and the composite parameter to the air and the water, selecting the sensitivity parameter to establish a three-dimensional drawing plate, and judging.

2. The method according to claim 1, wherein in S1, the preprocessing is to perform normalization processing on parameter curves with different scales in different periods by a normalization method, so that data of the parameter curves show determined response characteristics under the same geological condition.

3. The method for determining fluid in a tight gas reservoir according to claim 1, wherein in S2, the process of analyzing the parameter sensitivity through single parameter intersection and creating the composite parameter is as follows: based on the gas test data, the well logging data and the logging data, qualitatively analyzing the basic characteristics of a gas-water layer, and semi-quantitatively analyzing single parameters by using a conventional intersection plate method to obtain sensitive parameters; and combining different sensitive parameters, creating a composite parameter containing a plurality of sensitive parameter information, and carrying out pairwise intersection analysis.

4. The method for determining the sensitivity of a compact gas reservoir fluid according to claim 1, wherein in S3, the process of determining the sensitivity of the composite parameter and the single parameter to gas and water is as follows: and analyzing the sensitivity of the logging acoustic time difference AC, the stratum true resistivity RT, the density DEN, the logging total hydrocarbon QT, the porosity difference value SACQT comprehensive indexes, the acoustic time difference-compensating neutron AC-CNL envelope surface, the XQT gas-containing index and the POZ water-containing index by utilizing a radar chart to obtain the sensitivity interference factors of composite parameters and single parameters on gas and water, comparing to obtain sensitive parameters, and selecting the sensitive parameters to establish a three-dimensional chart.

5. The method of claim 1 or 4, wherein the composite parameters include SACQT comprehensive indices, AC-CNL envelope, XQT gas index, POZ water index.

6. The method for determining a fluid in a tight gas reservoir according to claim 4,

The SACQT comprehensive index is calculated as follows:

comprehensive index:

the XQT gas index was calculated as follows:

XQT gas index:

the POZ water index is calculated as follows:

POZ water index poz=f (Porw, SH, CNL, SW)

Wherein QT is logging whole hydrocarbon; AC is the logging acoustic time difference; Is normalized whole hydrocarbon; QT _min is the full hydrocarbon value; The normalized acoustic wave time difference; AC _min is the acoustic time difference base; h is the thickness of the intersection surface; h _QT is the gas measurement filling thickness; h _GR is sandstone thickness; porw is the aqueous porosity; SH is the clay content; CNL is compensation neutron; SW is water saturation.

7. The method according to claim 1 or 4, wherein the three-dimensional plate has a SACQT integrated index as an abscissa, a XQT gas index as an ordinate, and a POZ water index as an ordinate.

8. The method of claim 1, further comprising verification of a three-dimensional interpretation technique; the verification process is as follows: and (3) performing a return judgment on the established three-dimensional drawing plate to obtain a three-dimensional interpretation coincidence rate, comparing the two-dimensional single parameter coincidence rate, and verifying by using a new well.

9. A tight gas reservoir fluid discrimination system, comprising:

The data acquisition processing module is used for acquiring logging data and preprocessing the logging data to obtain standardized data;

the analysis module is used for analyzing the parameter sensitivity through single parameter intersection based on the standardized data and creating composite parameters;

and selecting and establishing a three-dimensional plate module, which is used for determining the sensitivity degree of single parameters and composite parameters to air and water, selecting the sensitive parameters, establishing a three-dimensional plate and judging.

10. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing the steps of the tight gas reservoir fluid discrimination method of any one of claims 1-8 when the computer program is executed.