Method, system, equipment and medium for identifying tight sandstone gas reservoir fluid

Abstract

The invention provides a method, a system, equipment and a medium for identifying tight sandstone gas reservoir fluid. The method comprises the following steps: collecting gas logging abnormal well section data and logging data of a target section; obtaining gas logging derivation parameters based on the gas logging abnormal well section data and the logging data, wherein the gas logging derivation parameters comprise a hydrocarbon slope and a humidity ratio; standard deviations of gas logging derived parameters of different reservoir sections are calculated; constructing a three-dimensional fluid identification chart according to the hydrocarbon slope, the humidity ratio and the standard deviation; according to the three-dimensional fluid identification plate, reservoir fluid properties are judged; according to the method, on the basis of fully considering the relationship between the gas logging derived parameters and the fluid types, the centralized dispersion degree of different reservoir derived parameters is introduced, and the three-dimensional chart is constructed based on the parameters, so that fluid identification is realized, and the problem that logging interpretation is difficult under the condition that gas logging display of part of wells is high but water is discharged through testing can be effectively solved.

Description

Technical Field

[0001] This invention relates to logging technology for oil and gas exploration, specifically to a method, system, equipment, and medium for identifying fluids in tight sandstone gas reservoirs. Background Technology

[0002] Well logging is an important means of discovering oil and gas shows in oil and gas exploration and development. Gas logging is an important branch of the logging profession. It is used to record drilling time and oil and gas composition data during the drilling process, and to evaluate the fluid properties of reservoirs with underground gas anomalies through these data, providing a basis for exploration and development decisions.

[0003] According to the search, there are currently three main types of methods for fluid identification based on gas logging data. The first type is to establish a chart for fluid identification using gas logging derived parameters. Examples include "Research and Application of New Gas Logging Interpretation Charts in the Keshen Area of ​​the Kuqa Depression" and "Research and Application of Gas Logging Technology in the Kuqa Depression". This type of method introduces the establishment of gas logging derived parameters using the full hydrocarbon curve, mainly including humidity ratio, hydrocarbon slope, trigonometric ratio, light-to-heavy ratio, etc. Then, mathematical methods such as principal component analysis are used to select parameters sensitive to fluid type to establish a chart, thereby achieving fluid identification.

[0004] The second method is to determine the properties of reservoir fluids by using the peak shape of well logging gas measurements. This method is mainly represented by patents such as "Method for Determining Reservoir Fluid Properties by Using the Peak Shape of Well Logging Gas Measurements (CN109403960A)", "A Method and Device for Identifying Oil Reservoir Types (CN108090653B)", papers such as "Several Examples of Identifying Gas Layers by Using Gas Measurement Curve Shapes", "Interpretation Method of Oil and Gas Showing Layers by Amplitude Difference Shape Method", and "Application Effect Analysis of Gas Layer Evaluation Method by Full Hydrocarbon Curve Shape in the Kongquehe Exploration Area". This type of method classifies the shape of continuous gas measurement curves and qualitatively analyzes the fluid types under different shapes. Some scholars have used mathematical methods to statistically analyze parameters such as skewness coefficient and kurtosis coefficient of curves under different shapes and used these parameters to establish fluid identification charts.

[0005] The third method is to combine logging data with the determination of reservoir fluid properties. This is mainly represented by patent "A method for identifying oil, gas and water based on the intersection of physical properties and gas logging parameters (CN1050411305A)" and paper "Quantitative calculation method of gas-oil ratio based on gas logging data". This type of method mainly uses gas logging data to construct special parameters and establish a fluid identification chart with porosity and other data interpreted from logging.

[0006] The reservoir gas logging in the Kelasu structural belt of the Kuqa Depression in the Tarim Basin shows development, but some wells have high gas logging data showing that the total hydrocarbon content of the reservoir section exceeds 50%, while the tested reservoir fluid is mainly water. When using conventional triangular chart methods, PXLER hydrocarbon ratio methods, light hydrocarbon ratio methods, gas logging derived parameters, and gas logging morphology evaluations to evaluate these phenomena, they are identified as typical gas layers, which does not match the test results. Therefore, it is urgent to develop and improve fluid identification methods based on gas logging data to solve the problem of well logging field interpretation. Summary of the Invention

[0007] To address the problems existing in the prior art, the present invention provides a method, system, equipment and medium for identifying fluids in tight sandstone gas reservoirs, in order to solve the technical problem of inaccurate identification of gas reservoir fluids in existing related technologies when the total hydrocarbon content of gas in the well reservoir section exceeds 50% and the fluid is mainly water.

[0008] This invention is achieved through the following technical solution:

[0009] A method for identifying fluids in tight sandstone gas reservoirs includes the following steps:

[0010] Collect gas logging anomaly data and well logging data for the target section;

[0011] Gas logging derived parameters are obtained based on gas logging anomaly well section data and well logging data. These gas logging derived parameters include hydrocarbon slope and moisture ratio.

[0012] Calculate the standard deviation of gas measurement derived parameters for different reservoir sections;

[0013] A three-dimensional fluid identification map is constructed based on hydrocarbon slope, humidity ratio, and standard deviation.

[0014] The properties of reservoir fluids are determined based on the three-dimensional fluid identification chart.

[0015] Furthermore, based on the reservoir division results from the well logging data, data from the corresponding gas logging anomaly segments are read.

[0016] Furthermore, the data in the gas measurement anomaly segment includes total hydrocarbons (TG), methane (C1), ethane (C2), propane (C3), n-butane (IC4), isobutane (NC4), n-pentane (IC5), and isopentane (NC5).

[0017] Furthermore, the process of obtaining gas logging derived parameters based on gas logging anomaly well section data and well logging data is as follows:

[0018] The hydrocarbon slope GH is:

[0019]

[0020] The humidity ratio WH is:

[0021]

[0022] In the formula, C1 represents methane gas measurement data (%); C2 represents ethane gas measurement data (%); C3 represents propane gas measurement data (%); IC4 represents n-butane gas measurement data (%); NC4 represents isobutane gas measurement data (%); IC5 represents n-pentane gas measurement data (%); and NC5 represents isopentane gas measurement data (%).

[0023] Furthermore, the process of calculating the standard deviation of gas-derived parameters for different reservoir sections is as follows:

[0024] When the reservoir is a gas layer, the hydrocarbon slope and moisture ratio data are very concentrated in the chart. However, when the reservoir is a gas-water co-layer or a gas-water layer, the hydrocarbon slope and moisture ratio data are relatively dispersed in the chart. The standard deviation XS is used to perform quantitative standard to characterize this phenomenon.

[0025] Gas-derived parameters were collected for each well, confirming it as a gas layer, gas-water co-layer, gas-water-bearing layer, and water layer. The standard deviations for each well's gas layer, gas-water co-layer, gas-water-bearing layer, and water layer were calculated.

[0026]

[0027]

[0028] In the formula, n is the number of columns in the array, and m is the number of data items in each column. This represents the average value of the data in each column.

[0029] Furthermore, the process of constructing a three-dimensional fluid identification map based on hydrocarbon slope, humidity ratio, and standard deviation is as follows:

[0030] A three-dimensional fluid identification chart is established with hydrocarbon slope as the X-axis, moisture ratio as the Y-axis, and standard deviation XS as the Z-axis. The standard deviation of the derived parameter array for each well is the same.

[0031] Furthermore, the process of determining the reservoir fluid properties based on the three-dimensional fluid identification map is as follows:

[0032] The gas logging derived parameters and standard deviation parameters of the target well are projected onto the three-dimensional fluid identification chart, and the fluid type is determined based on the landing area.

[0033] The process of determining the fluid type based on the landing area is as follows:

[0034] If the standard deviation of the measured target well is greater than 1, the fluid type of the measured target well is an aquifer; if the standard deviation is less than 1, the fluid type of the measured target well is a gas layer.

[0035] A system for identifying fluids in tight sandstone gas reservoirs includes:

[0036] The data acquisition module is configured as follows:

[0037] Used to collect gas logging anomaly data and logging data for the target section;

[0038] The first processing module is configured as follows:

[0039] This is used to obtain gas logging derived parameters based on gas logging anomaly well section data and logging data, wherein the gas logging derived parameters include hydrocarbon slope and moisture ratio;

[0040] The second processing module is configured as follows:

[0041] Used to calculate the standard deviation of gas measurement derived parameters for different reservoir sections;

[0042] The image creation module is configured as follows:

[0043] Used to construct a three-dimensional fluid identification map based on hydrocarbon slope, humidity ratio, and standard deviation;

[0044] The output module is configured as follows:

[0045] Used to determine the properties of reservoir fluids based on the three-dimensional fluid identification chart.

[0046] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of a method for identifying fluids in a tight sandstone gas reservoir as described above.

[0047] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of a method for identifying fluids in a tight sandstone gas reservoir.

[0048] Compared with the prior art, the present invention has the following beneficial technical effects:

[0049] This invention provides a method, system, equipment, and medium for identifying fluids in tight sandstone gas reservoirs, comprising the following steps: collecting gas logging anomaly data and well logging data of the target section; obtaining gas logging derived parameters based on the gas logging anomaly data and well logging data, wherein the gas logging derived parameters include hydrocarbon slope and moisture ratio; calculating the standard deviation of the gas logging derived parameters for different reservoir sections; constructing a three-dimensional fluid identification chart based on the hydrocarbon slope, moisture ratio, and standard deviation; and judging the reservoir fluid properties based on the three-dimensional fluid identification chart. This application, by fully considering the relationship between gas logging derived parameters and fluid type, introduces the concentration and dispersion degrees of different reservoir derived parameters and constructs a three-dimensional chart based on these parameters, realizing fluid identification and effectively solving the problem of difficult logging interpretation when some wells show high gas logging but produce water during testing. Attached Figure Description

[0050] Figure 1 A flowchart illustrating a method for identifying fluids in tight sandstone gas reservoirs according to an embodiment of this disclosure is shown.

[0051] Figure 2 A three-dimensional fluid identification diagram based on humidity ratio and hydrocarbon slope is shown according to an embodiment of this disclosure;

[0052] Figure 3 This illustration shows a three-dimensional fluid identification diagram based on gas measurement derived parameters and standard deviation, according to an embodiment of this disclosure. Figure 4 An embodiment of the present disclosure illustrates a system for identifying fluids in tight sandstone gas reservoirs. Detailed Implementation

[0053] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0054] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0055] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0056] In this embodiment, the Cretaceous tight sandstone oil and gas reservoir in the foreland basin of the Tarim Basin is a major domestic gas source. The lithology is mainly fine sandstone and gravelly sandstone, and the porosity of the core analysis is 4%-12%. The gas logging of the reservoir section shows good results. However, in the actual interpretation process, it was found that some wells showed good gas logging results, and the total hydrocarbons in the gas logging of some reservoir sections exceeded 50%. The test confirmed that the fluid type was mainly water. When using conventional triangular chart method, PXLER hydrocarbon ratio method, light hydrocarbon ratio method, gas logging derived parameters and gas logging morphology evaluation, it was identified as a typical gas layer, which is inconsistent with the test results.

[0057] Figure 1 A flowchart of a method 100 for identifying fluids in tight sandstone gas reservoirs according to an embodiment of the present disclosure is shown. The embodiment of the present disclosure includes the following steps:

[0058] S101: Collect gas logging anomaly data and well logging data for the target section;

[0059] S102: Based on gas logging anomaly well section data and logging data, gas logging derived parameters are obtained, including hydrocarbon slope and moisture ratio;

[0060] S103: Calculate the standard deviation of gas measurement derived parameters for different reservoir sections;

[0061] S104: Construct a three-dimensional fluid identification map based on hydrocarbon slope, humidity ratio, and standard deviation;

[0062] S105: Determine the properties of the reservoir fluid based on the three-dimensional fluid identification chart.

[0063] Preferably, in this embodiment of the disclosure, the data of the gas logging anomaly segment corresponding to the reservoir segment is read based on the result of dividing the reservoir according to the well logging data;

[0064] Specifically, gas logging anomalies typically involve phenomena that occur when encountering oil and gas reservoirs during drilling. These anomalies result from gases in the fractured rock layers and formations seeping into the drilling fluid through filtration or diffusion. On the logging curve, gas logging anomalies manifest as a significant increase in total hydrocarbon content compared to the background gas logging value (base value). The base value is the relatively stable average gas logging value, which is a small, slow increase caused by some gases from the upper formation intruding into the drilling fluid under pressure equilibrium conditions. Generally, the determination of gas logging anomalies depends on the size of the base value. For example, when the base value is less than 1%, the total hydrocarbon content is 2 times or more than the base value; when the base value is between 1% and 10%, the total hydrocarbon content is 1.5 times or more than the base value; and when the base value is greater than 10%, the total hydrocarbon content is 1.2 times or more than the background total hydrocarbon value (base value).

[0065] The data of gas logging anomalies are reflected in the logging curve as an increase in the amplitude of the curve, indicating an increase in the total amount of alkane in the drilling fluid. This may be due to formation oil and gas type, aftereffect gas type, single gas type, crude oil mixed type, or mixed type. Different types of anomalies may have different characteristics on the logging curve. For example, the downward process and upward process of formation oil and gas anomalies after the peak are basically the same, showing symmetry.

[0066] Furthermore, in this embodiment of the disclosure, the data of the gas measurement anomaly segment includes total hydrocarbons (TG), methane (C1), ethane (C2), propane (C3), n-butane (IC4), isobutane (NC4), n-pentane (IC5), and isopentane (NC5).

[0067] Preferably, in this embodiment of the disclosure, the process of obtaining gas logging derived parameters based on gas logging anomaly well section data and well logging data is as follows:

[0068] The hydrocarbon slope GH is:

[0069]

[0070] The humidity ratio WH is:

[0071]

[0072] In the formula, C1 represents methane gas measurement data (%); C2 represents ethane gas measurement data (%); C3 represents propane gas measurement data (%); IC4 represents n-butane gas measurement data (%); NC4 represents isobutane gas measurement data (%); IC5 represents n-pentane gas measurement data (%); and NC5 represents isopentane gas measurement data (%).

[0073] Specifically, the gas measurement data described in this embodiment is based on the use of a hydrogen flame ionization detector to generate many ion pairs by ionizing organic matter in a hydrogen flame. An ion current is formed between two electrodes with a certain voltage applied. The intensity of the ion current can be measured to detect the component. The percentage is the ion current intensity of the corresponding component divided by the ion current intensity of the entire component.

[0074] It should be noted that the hydrocarbon slope mainly reflects the content and variation trend of hydrocarbon components in the formation. Changes in the hydrocarbon slope can help determine the existence and distribution of oil and gas layers. By comparing hydrocarbon slope data at different depths, areas with high hydrocarbon content can be identified, thereby determining the thickness and distribution of oil and gas layers.

[0075] The humidity ratio mainly reflects the ratio of water vapor content to total gas content in the formation. Humidity ratio data can be used to determine the humidity conditions of the formation, thereby inferring the water content and permeability of the formation. For oil and gas reservoirs, changes in the humidity ratio can reveal the relative relationship between oil and gas and water, which helps to identify the oil-gas-water interface and determine the reservoir performance of oil and gas reservoirs.

[0076] Preferably, in this embodiment of the disclosure, the process of calculating the standard deviation of gas-derived parameters for different reservoir sections is as follows:

[0077] When the reservoir is a gas layer, the hydrocarbon slope and moisture ratio data are very concentrated in the chart. However, when the reservoir is a gas-water co-layer or a gas-water layer, the hydrocarbon slope and moisture ratio data are relatively dispersed in the chart. The standard deviation XS is used to perform quantitative standard to characterize this phenomenon.

[0078] Gas-derived parameters were collected for each well, confirming it as a gas layer, gas-water co-layer, gas-water-bearing layer, and water layer. The standard deviations for each well's gas layer, gas-water co-layer, gas-water-bearing layer, and water layer were calculated.

[0079]

[0080]

[0081] In the formula, n is the number of columns in the array, and m is the number of data items in each column. This represents the average value of the data in each column.

[0082] Preferably, in this embodiment of the disclosure, the process of constructing a three-dimensional fluid identification map based on hydrocarbon slope, humidity ratio, and standard deviation is as follows:

[0083] A three-dimensional fluid identification chart is established with the hydrocarbon slope as the X-axis, the moisture ratio as the Y-axis, and the standard deviation XS as the Z-axis. The standard deviation of the derived parameter array for each well is the same. Figure 2The diagram shows a three-dimensional fluid identification chart based on humidity ratio and hydrocarbon slope according to an embodiment of the present disclosure. As can be seen from the diagram, wells X15 and X902, which tested for producing water, and wells X9, X16, and X903, which tested for producing gas, are all in the same area, making it impossible to effectively distinguish the fluid type.

[0084] The process of determining the reservoir fluid properties based on the three-dimensional fluid identification map is as follows:

[0085] The gas logging derived parameters and standard deviation parameters of the target well are projected onto the three-dimensional fluid identification chart, and the fluid type is determined based on the landing area.

[0086] The process of determining the fluid type based on the landing area is as follows:

[0087] If the standard deviation of the measured target well is greater than 1, the fluid type of the measured target well is an aquifer; if the standard deviation is less than 1, the fluid type of the measured target well is a gas layer.

[0088] Figure 3 The diagram illustrates a three-dimensional fluid identification chart based on gas logging derived parameters and standard deviations according to an embodiment of this disclosure. As can be seen from the diagram, wells X9, X903, and X16 are gas-bearing zones with standard deviations (XS) less than 1, while wells X15, X30, X902, and X903 are gas-bearing and water-bearing zones with standard deviations greater than 1. This invention effectively distinguishes between gas-bearing and non-gas-bearing zones, significantly improving the logging interpretation accuracy of this block.

[0089] Figure 4 A system 1000 for identifying fluids in tight sandstone gas reservoirs, according to an embodiment of this disclosure, is shown, comprising:

[0090] Acquisition module 1001 is configured as follows:

[0091] Used to collect gas logging anomaly data and logging data for the target section;

[0092] The first processing module 1002 is configured as follows:

[0093] This is used to obtain gas logging derived parameters based on gas logging anomaly well section data and logging data, wherein the gas logging derived parameters include hydrocarbon slope and moisture ratio;

[0094] The second processing module 1003 is configured as follows:

[0095] Used to calculate the standard deviation of gas measurement derived parameters for different reservoir sections;

[0096] The drawing creation module 1004 is configured as follows:

[0097] Used to construct a three-dimensional fluid identification map based on hydrocarbon slope, humidity ratio, and standard deviation;

[0098] Output module 1005 is configured as follows:

[0099] Used to determine the properties of reservoir fluids based on the three-dimensional fluid identification chart.

[0100] In another embodiment of the present invention, a computer device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used in the operation of a method for identifying fluids in tight sandstone gas reservoirs.

[0101] In another embodiment of the present invention, a storage medium is provided, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the operating system of the terminal. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor, which can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the method for identifying fluids in tight sandstone gas reservoirs in the above embodiments.

[0102] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can 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, etc.) containing computer-usable program code.

[0103] This 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 block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can 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, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0104] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0105] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for identifying fluids in tight sandstone gas reservoirs, characterized in that, Includes the following steps: Collect gas logging anomaly data and well logging data for the target section; Gas logging derived parameters are obtained based on gas logging anomaly well section data and well logging data. These gas logging derived parameters include hydrocarbon slope and moisture ratio. Calculate the standard deviation of gas measurement derived parameters for different reservoir sections; A three-dimensional fluid identification map is constructed based on hydrocarbon slope, humidity ratio, and standard deviation. The properties of reservoir fluids are determined based on the three-dimensional fluid identification chart.

2. The method for identifying fluids in tight sandstone gas reservoirs according to claim 1, characterized in that, Based on the reservoir division results from well logging data, data from the corresponding gas logging anomaly segments are read.

3. The method for identifying fluids in tight sandstone gas reservoirs according to claim 1, characterized in that, The data from the gas measurement anomaly segment include total hydrocarbons (TG), methane (C1), ethane (C2), propane (C3), n-butane (IC4), isobutane (NC4), n-pentane (IC5), and isopentane (NC5).

4. The method for identifying fluids in tight sandstone gas reservoirs according to claim 1, characterized in that, The process of obtaining gas logging derived parameters based on gas logging anomaly well section data and well logging data is as follows: The hydrocarbon slope GH is: The humidity ratio WH is: In the formula, C1 represents methane gas measurement data, %; C2 represents ethane gas measurement data, %; and C3 represents propane gas measurement data, %; IC4 represents n-butane gas measurement data, %; NC4 represents isobutane gas measurement data, %; IC5 represents n-pentane gas measurement data, %; NC5 represents isopentane gas measurement data, %.

5. The method for identifying fluids in tight sandstone gas reservoirs according to claim 1, characterized in that, The process for calculating the standard deviation of gas-derived parameters for different reservoir sections is as follows: When the reservoir is a gas layer, the hydrocarbon slope and moisture ratio data are very concentrated in the chart. However, when the reservoir is a gas-water co-layer or a gas-water layer, the hydrocarbon slope and moisture ratio data are relatively dispersed in the chart. The standard deviation XS is used to perform quantitative standard to characterize this phenomenon. Gas-derived parameters were collected for each well, confirming it as a gas layer, gas-water co-layer, gas-water-bearing layer, and water layer. The standard deviations for each well's gas layer, gas-water co-layer, gas-water-bearing layer, and water layer were calculated. In the formula, n is the number of columns in the array, and m is the number of data items in each column. This represents the average value of the data in each column.

6. The method for identifying fluids in tight sandstone gas reservoirs according to claim 1, characterized in that, The process of constructing a three-dimensional fluid identification map based on hydrocarbon slope, humidity ratio, and standard deviation is as follows: A three-dimensional fluid identification chart is established with hydrocarbon slope as the X-axis, moisture ratio as the Y-axis, and standard deviation XS as the Z-axis. The standard deviation of the derived parameter array for each well is the same.

7. The method for identifying fluids in tight sandstone gas reservoirs according to claim 1, characterized in that, The process of determining the reservoir fluid properties based on the three-dimensional fluid identification map is as follows: The gas logging derived parameters and standard deviation parameters of the target well are projected onto the three-dimensional fluid identification chart, and the fluid type is determined based on the landing area. The process of determining the fluid type based on the landing area is as follows: If the standard deviation of the measured target well is greater than 1, the fluid type of the measured target well is an aquifer; if the standard deviation is less than 1, the fluid type of the measured target well is a gas layer.

8. A system for identifying fluids in tight sandstone gas reservoirs, characterized in that, A method for identifying fluids in tight sandstone gas reservoirs according to any one of claims 1-7, comprising: The data acquisition module is configured as follows: Used to collect gas logging anomaly data and logging data for the target section; The first processing module is configured as follows: This is used to obtain gas logging derived parameters based on gas logging anomaly well section data and logging data, wherein the gas logging derived parameters include hydrocarbon slope and moisture ratio; The second processing module is configured as follows: Used to calculate the standard deviation of gas measurement derived parameters for different reservoir sections; The image creation module is configured as follows: Used to construct a three-dimensional fluid identification map based on hydrocarbon slope, humidity ratio, and standard deviation; The output module is configured as follows: Used to determine the properties of reservoir fluids based on the three-dimensional fluid identification chart.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of a method for identifying fluids in tight sandstone gas reservoirs as described in any one of claims 1-7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of a method for identifying fluids in tight sandstone gas reservoirs as described in any one of claims 1-7.

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