Method and system for determining mantle source argon input characteristics in geological fluid and oil and gas reservoir state

Abstract

The application relates to the technical field of geological fluid analysis, and discloses a mantle source argon input characteristic and oil and gas reservoir state determination method and system in geological fluid, which comprises the following steps: collecting a geological fluid sample of an oil and gas reservoir area; detecting the gas argon isotope composition in the geological fluid sample to obtain the measured ratio of mixed argon 40 Ar and 36 Ar; determining the geological time experienced by the source stratum based on the era in which the source stratum of the geological fluid sample is located; calculating the theoretical ratio of stratum background argon 40 Ar and 36 Ar in the source stratum based on the geological time; determining the excess argon coefficient based on the measured ratio and the theoretical ratio; in the case that the excess argon coefficient is greater than or equal to a preset threshold value, calculating the input proportion of mantle source argon in the geological fluid sample based on the measured ratio, the theoretical ratio and the standard ratio of mantle end-member argon 40 Ar and 36 Ar; and determining the activity characteristic and the oil and gas reservoir state of the target geological fluid in the oil and gas reservoir area based on the input proportion.

Description

Technical Field

[0001] This application relates to the field of geological fluid analysis technology, and relates to, but is not limited to, a method and system for determining the characteristics of mantle-derived argon input in geological fluids and the state of oil and gas reservoirs. Background Technology

[0002] Earth is an interconnected whole with a multi-layered structure. Earth's evolution is a process of continuous interaction between different spheres. During this process, the vast amounts of carbon, hydrogen, oxygen, and sulfur in the mantle, mediated by geological fluids, continuously traverse multiple spheres, diffusing from deep to shallow layers. This inter-sphere exchange of matter and energy strongly influences the Earth's surface topography, land-sea changes, climate change, marine environment, the origin and evolution of life, and the formation of resources, energy, and minerals. Therefore, identifying the input characteristics of mantle-derived (i.e., mantle-sourced) materials in shallow strata is of great significance for geological disaster prevention, metallic mineral exploration, and oil and gas resource exploration.

[0003] Among related technologies, the means for identifying the deep source of geological fluids and evaluating their activity characteristics are relatively limited. It is difficult to accurately and quantitatively characterize the degree of mantle-derived argon mixing in geological fluids, and it is difficult to establish a precise correspondence between the activity characteristics of deep mantle fluids and the disturbance and alteration status of oil and gas reservoirs. Summary of the Invention

[0004] In view of this, embodiments of this application provide a method and system for determining the characteristics of mantle-derived argon input in geological fluids and the state of oil and gas reservoirs, which at least solves the problem that it is difficult to accurately determine the proportion of mantle-derived argon input in geological fluids and that it is impossible to quantitatively determine the degree of mixing of deep mantle fluids with the state of oil and gas reservoirs.

[0005] The technical solution of this application embodiment is implemented as follows: In a first aspect, embodiments of this application provide a method for determining the characteristics of mantle-derived argon input in geological fluids and the state of hydrocarbon reservoirs, the method comprising: Collect target geological fluid samples from the target oil and gas reservoir area; The gaseous argon isotope composition in the target geological fluid sample was detected using a rare gas mass spectrometer. Based on the gaseous argon isotope composition, the mixed argon content in the target geological fluid sample was determined. 40 Ar and 36 The measured ratio of Ar, wherein the mixed argon includes atmospheric argon, radiogenic argon and mantle-derived argon; Based on the age of the source strata of the target geological fluid sample, determine the geological time experienced by the source strata; Based on the geological time, calculate the background argon in the source strata. 40 Ar and 36The theoretical ratio of Ar, wherein the background argon of the formation includes atmospheric argon and radiogenic argon; The excess argon coefficient is determined based on the measured ratio and the theoretical ratio. When the excess argon coefficient is greater than or equal to a preset threshold, based on the measured ratio, the theoretical ratio, and the mantle end-member argon... 40 Ar and 36 The standard ratio of Ar is used to calculate the input proportion of mantle-derived argon in the target geological fluid sample; Based on the input ratio of mantle-sourced argon, the activity characteristics of the target geological fluid and the state of the oil and gas reservoir within the target oil and gas reservoir area are determined.

[0006] In some embodiments, the background argon in the source strata is calculated using the following formula. 40 Ar and 36 Theoretical ratio of Ar: ; in, 40 Ar is an isotope of argon-40. 36 Ar is an isotope of argon-36. The theoretical ratio is given, and T is the geological time.

[0007] In some embodiments, the excess argon coefficient is determined by calculating the following formula: ; in, The measured ratio is... This is the excess argon coefficient.

[0008] In some embodiments, the input proportion of mantle-derived argon in the target geological fluid sample is calculated using the following formula: ; in, The input ratio of mantle-sourced argon. Argon for the mantle endmember 40 Ar and 36 The standard ratio of Ar.

[0009] In some embodiments, the target geological fluid includes primary formation fluid and deep mantle fluid, wherein the deep mantle fluid upwells along tectonic channels and mixes with the primary formation fluid. Based on the input ratio of mantle-derived argon, the activity characteristics of the target geological fluid and the reservoir status within the target oil and gas reservoir area are determined, including: When the input ratio of mantle-sourced argon is less than 3%, it is determined that the target geological fluid activity in the target oil and gas reservoir area is weak and the oil and gas reservoir structure is stable. When the input ratio of mantle-source argon is greater than or equal to 3% and less than 10%, it is determined that the target geological fluid is in a weakly active state and the oil and gas reservoir is slightly disturbed. When the input ratio of mantle-source argon is greater than or equal to 10%, it is determined that the target geological fluid activity is strong and the oil and gas reservoir is significantly affected by deep mantle fluids.

[0010] Secondly, embodiments of this application provide a system for determining the characteristics of mantle-derived argon input in geological fluids and the state of hydrocarbon reservoirs, the system comprising: The acquisition module is used to collect target geological fluid samples from the target oil and gas reservoir area; The detection module is used to detect the gaseous argon isotope composition in the target geological fluid sample using a rare gas mass spectrometer. The first determining module is used to determine the mixed argon content in the target geological fluid sample based on the gaseous argon isotope composition. 40 Ar and 36 The measured ratio of Ar, wherein the mixed argon includes atmospheric argon, radiogenic argon and mantle-derived argon; The second determining module is used to determine the geological time experienced by the source stratum based on the age of the source stratum of the target geological fluid sample. The first calculation module is used to calculate the background argon in the source strata based on the geological time. 40 Ar and 36 The theoretical ratio of Ar, wherein the background argon of the formation includes atmospheric argon and radiogenic argon; The third determining module is used to determine the excess argon coefficient based on the measured ratio and the theoretical ratio; The second calculation module is used to, when the excess argon coefficient is greater than or equal to a preset threshold, calculate based on the measured ratio, the theoretical ratio, and the mantle end-member argon. 40 Ar and 36 The standard ratio of Ar is used to calculate the input proportion of mantle-derived argon in the target geological fluid sample; The fourth determination module is used to determine the activity characteristics of the target geological fluid and the state of the oil and gas reservoir within the target oil and gas reservoir area based on the input ratio of the mantle-sourced argon.

[0011] In some embodiments, the target geological fluid includes primary stratigraphic fluid and deep mantle fluid, wherein the deep mantle fluid upwells along tectonic channels and mixes with the primary stratigraphic fluid. The fourth determining module includes: The first determination submodule is used to determine that the target geological fluid activity in the target oil and gas reservoir area is weak and the oil and gas reservoir structure is stable when the input ratio of mantle-source argon is less than 3%. The second determination submodule is used to determine that the target geological fluid is in a weakly active state and the oil and gas reservoir is slightly disturbed when the input ratio of the mantle-sourced argon is greater than or equal to 3% and less than 10%. The third determination submodule is used to determine, when the input ratio of mantle-source argon is greater than or equal to 10%, that the target geological fluid activity is strong and the oil and gas reservoir is significantly affected by deep mantle fluids.

[0012] The beneficial effects of the technical solutions provided in this application include at least the following: This application embodiment uses a rare gas mass spectrometer to detect the argon isotope composition in geological fluids, accurately distinguishing three types of endmembers: atmospheric argon, radiogenic argon, and mantle-derived argon. It establishes a correlation between geological time and the evolution of argon background in the stratigraphy, calculates the excess argon coefficient by comparing measured and theoretical ratios, and then quantitatively inverts the input ratio of mantle-derived argon based on the standard ratio of mantle endmembers. Ultimately, it achieves the determination of geological fluid activity characteristics and oil and gas reservoir status, accurately distinguishing multiple endmember argon sources, realizing quantitative and accurate evaluation of deep mantle fluid activity, and improving the objectivity, accuracy, and systematicness of the determination. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 A flowchart illustrating a method for determining the characteristics of mantle-derived argon input in geological fluids and the state of oil and gas reservoirs, provided for embodiments of this application; Figure 2 A target geological fluid provided in the embodiments of this application 40 Ar and 36 A schematic diagram of the measured ratio, theoretical ratio, and geological time of Ar; Figure 3 A schematic diagram illustrating the input ratio of mantle-source argon to a target geological fluid, provided for an embodiment of this application; Figure 4 This is a schematic diagram of the composition and structure of a geological fluid mantle-derived argon input characteristic and oil and gas reservoir state determination system provided in an embodiment of this application. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. The following embodiments are used to illustrate this application, but are not intended to limit the scope of this application. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0015] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0016] It should be noted that the terms "first, second, and third" used in the embodiments of this application are merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, and third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0017] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of this application pertain. It should also be understood that terms such as those defined in general dictionaries should be understood to have a meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0018] This application provides a method and system for determining the characteristics of mantle-derived argon input in geological fluids and the state of oil and gas reservoirs, applicable to electronic devices. These electronic devices include, but are not limited to, mobile phones, laptops, tablets, handheld internet devices, multimedia devices, streaming media devices, mobile internet devices, wearable devices, or other types of electronic devices. The functions implemented by this method can be achieved by a processor in the electronic device calling program code. The program code can be stored in a computer storage medium; therefore, the electronic device includes at least a processor and a storage medium. The processor can be used to process the determination of the characteristics of mantle-derived argon input in geological fluids and the state of oil and gas reservoirs, while the memory can be used to store the data required and generated during the determination process.

[0019] Figure 1 This is a schematic diagram illustrating a method for determining the characteristics of mantle-derived argon input in geological fluids and the state of hydrocarbon reservoirs, as provided in an embodiment of this application.Figure 1 As shown, the method includes at least the following steps: Step S110: Collect target geological fluid samples from the target oil and gas reservoir area; The target oil and gas reservoirs are underground oil and gas rich areas, including the Keqiya Gas Field in southwestern Tarim Basin, the Hotanhe Gas Field in southwestern Tarim Basin, the Anyue Gas Field in Sichuan Basin, the Songliao Basin, and the Mabei Gas Field in Qaidam Basin. The target geological fluid samples are representative samples of the target geological fluids, including natural gas samples, hot spring gas samples, geothermal fluid desolvated gas samples, and gas inclusions in rocks. Different collection and extraction methods are used for target geological fluids in different occurrence states. For example, for natural gas samples, the cylinder sampling method is used, using natural gas sampling cylinders and sampling pipelines to collect samples at the natural gas wellhead; for hot spring gas samples or geothermal fluid desolvated gas samples, the glass bottle water drainage gas collection method is used; and for gas inclusions in rocks, the vacuum electromagnetic fracturing method is used to extract the gas samples from the rocks.

[0020] Step S120: Use a rare gas mass spectrometer to detect the gaseous argon isotope composition in the target geological fluid sample; Among them, the rare gas mass spectrometer is used to detect isotopes of rare gases such as argon and helium. Natural argon contains a variety of isotopes. In the embodiments of this application, a stable and highly abundant argon isotope can be selected: argon-40 ( 40 Ar) and Ar-36 ( 36 Ar) is used as the detection object to determine the relative content of the two in the target geological fluid sample.

[0021] Step S130: Based on the gaseous argon isotope composition, determine the mixed argon content in the target geological fluid sample. 40 Ar and 36 The measured ratio of Ar, wherein the mixed argon includes atmospheric argon, radiogenic argon and mantle-derived argon; The mixed argon comprises atmospheric argon and radiogenic argon present in the original fluids of the strata, mixed with mantle-derived argon carried by deep mantle fluids. The atmospheric argon is argon carried by surface air as it infiltrates the strata with the target geological fluids. The radiogenic argon is argon generated from the long-term radioactive decay of potassium in the strata, and its content accumulates with the age of the strata. The mantle-derived argon is mantle-originating argon, brought into the strata by deep mantle fluids flowing up along faults and channels, and can mix with the mixed argon. 40 Ar and 36 The ratio of the relative contents of Ar was determined as the measured ratio.

[0022] Step S140: Determine the geological time experienced by the source strata based on the age of the source strata of the target geological fluid sample; Specifically, the geological time T1 can be determined by consulting regional geological maps, stratigraphic reports, drilling and logging data, and exploration reports of the study area, or by examining the fossil and lithological characteristics of the source strata. For natural gas samples, the geological time T2 can be determined by investigating the age of the source rock strata. For hot spring gas / geothermal fluid desolvation gas, the geological time T2 can be determined by investigating the age of the strata. For rock inclusion gas, the geological time T3 can be determined by investigating the sedimentary age (sedimentary rocks) or magmatic intrusion age (igneous rocks). The International Geological Time Table records the start and end dates of each geological age. The geological time of the corresponding source strata can be found by referring to the International Geological Time Table.

[0023] Step S150: Based on the geological time, calculate the background argon content in the source strata. 40 Ar and 36 The theoretical ratio of Ar, wherein the background argon of the formation includes atmospheric argon and radiogenic argon; Among them, the background argon of the formation refers to the primary argon of the formation excluding interference from mantle-derived argon. The atmospheric argon in the formation mainly comes from the atmosphere dissolved by the original formation water during the formation of the formation, and its input is relatively stable; radiogenic argon mainly originates from potassium ( 40 The radioactive decay of K (potassium-40 isotope) has a chronological accumulation effect; therefore, in the absence of mantle-sourced argon input, the mixture of atmospheric and radiogenic argon in the strata... 40 Ar / 36 The theoretical ratio of Ar is linearly related to the geological time elapsed since the formation of the strata. Therefore, the background argon content of the strata can be determined based on geological time. 40 Ar and 36 The theoretical ratio of Ar.

[0024] Step S160: Determine the excess argon coefficient based on the measured ratio and the theoretical ratio; The excess argon coefficient is used to characterize the degree of deviation of argon isotopes in the target geological fluid sample from the background state of the strata, thereby reflecting the mixing of deep mantle-derived argon.

[0025] Step S170: When the excess argon coefficient is greater than or equal to a preset threshold, based on the measured ratio, the theoretical ratio, and the mantle end-member argon... 40 Ar and 36 The standard ratio of Ar is used to calculate the input proportion of mantle-derived argon in the target geological fluid sample; The mantle endmember argon is an ideally pure, uncontaminated deep mantle primary argon component, unaffected by crustal fluids or atmospheric components. It serves as the theoretical benchmark endmember for isotope mixing calculations and adopts globally recognized fixed endmembers. 40 Ar and36 The standard ratio of Ar, the preset threshold can be 1. When the excess argon coefficient is less than 1, it indicates that there is no mantle-source argon input in the target geological fluid sample. When the excess argon coefficient is greater than or equal to 1, it indicates that there are signs of mantle-source argon input in the target geological fluid sample. The proportion of mantle-source argon input can be calculated by combining the measured ratio, the theoretical ratio and the standard ratio of mantle end-member argon. Specifically, when the excess argon coefficient is greater than or equal to 1 and less than or equal to 2, it indicates that there is suspected mantle-source argon input in the target geological fluid sample. When the excess argon coefficient is greater than 2, it indicates that there is confirmed mantle-source argon input in the target geological fluid sample.

[0026] Step S180: Based on the input ratio of the mantle-sourced argon, determine the activity characteristics of the target geological fluid and the state of the oil and gas reservoir within the target oil and gas reservoir area.

[0027] Among them, the activity intensity of target geological fluids in the target oil and gas reservoir area can be inverted by the proportion of mantle-sourced argon input, and the stability state of the corresponding oil and gas reservoir can be evaluated.

[0028] In the above embodiments, the argon isotope composition in geological fluids is detected by rare gas mass spectrometry, accurately distinguishing three types of endmembers: atmospheric argon, radiogenic argon, and mantle-derived argon. The correlation between geological time and the evolution of argon background in the stratigraphy is established. The excess argon coefficient is calculated by comparing the measured ratio with the theoretical ratio. Then, the input ratio of mantle-derived argon is quantitatively inverted based on the standard ratio of mantle endmembers. Finally, the characteristics of geological fluid activity and the state of oil and gas reservoirs are determined. This method can accurately distinguish the argon sources of multiple endmembers, realize the quantitative and accurate evaluation of deep mantle fluid activity, and improve the objectivity, accuracy, and systematicness of the determination.

[0029] In some embodiments, in step S150, the background argon in the source strata is calculated using the following formula (1). 40 Ar and 36 Theoretical ratio of Ar: Formula (1); in, 40 Ar is an isotope of argon-40. 36 Ar is an isotope of argon-36. The theoretical ratio is dimensionless, and T is the geological time in millions of years.

[0030] It should be noted that formula (1) is an empirical formula obtained by statistical fitting of measured natural gas samples from major sedimentary basins in China. This empirical formula characterizes the geological time of natural gas source rock formation and the background argon content of the strata. 40 Ar and 36The quantitative correlation of the theoretical ratio of Ar; based on the geological time corresponding to the target reservoir strata, the background argon of the strata containing only atmospheric argon and radiogenic argon can be calculated by substituting into this empirical formula. 40 Ar and 36 The theoretical ratio of Ar. In the above embodiments, the geological time and the background argon of the formation are established based on the laws of radioactive decay. 40 Ar and 36 The quantitative relationship of the theoretical ratio of Ar can accurately calculate the evolution of primary argon isotopes in strata during different geological periods, effectively eliminate the background signal interference caused by differences in strata age, realize unified correction and comparison of strata of different ages, and improve the accuracy and versatility of strata background correction by using simple model parameters and convenient calculation. It provides reliable basic data support for subsequent identification of excess argon and quantitative calculation of mantle-derived argon.

[0031] In some embodiments, in step S160, the excess argon coefficient is calculated and determined using the following formula (2): Formula (2); in, The measured ratio is dimensionless. The excess argon coefficient is dimensionless.

[0032] In the above embodiments, the excess argon coefficient is constructed by normalizing the measured ratio and the theoretical ratio of argon isotopes. This can directly amplify the mantle-derived argon anomaly signal, realize the quantitative characterization of the degree of mantle-derived argon anomaly, and enable horizontal comparison and hierarchical evaluation of mantle-derived argon anomalies in different target geological fluid samples and different blocks. The index is unique, the calculation is simple, and the results are objective, avoiding the subjectivity of human experience judgment and improving the reliability and accuracy of mantle-derived argon anomaly identification.

[0033] In some embodiments, in step S170, the input ratio of mantle-derived argon in the target geological fluid sample is calculated using the following formula (3): Formula (3); in, The input ratio of mantle-sourced argon. Argon for the mantle endmember 40 Ar and 36 The standard ratio of Ar can be set to 15000. The input ratio of mantle-sourced argon can reflect the degree to which deep mantle fluids from the mantle and deep layers mix into the target oil and gas reservoir.

[0034] In the above embodiments, the standard ratio of mantle end-member argon is introduced, which can accurately calculate the input ratio of mantle-source argon in geological fluids, transform qualitative anomaly judgment into quantitative contribution evaluation, clarify the degree of mixing of deep mantle fluids, and make the model's physical meaning clear and the calculation rigorous, effectively reducing ambiguity and realizing accurate quantitative characterization of the intensity of deep mantle fluid activity.

[0035] In some embodiments, the target geological fluid includes primary formation fluid and deep mantle fluid, wherein the deep mantle fluid flows up along tectonic channels and mixes with the primary formation fluid. "Step S180, determining the activity characteristics of the target geological fluid and the reservoir status within the target oil and gas reservoir area based on the input ratio of the mantle-derived argon" includes: Step S1801: When the input ratio of mantle-sourced argon is less than 3%, it is determined that the target geological fluid activity in the target oil and gas reservoir area is weak and the oil and gas reservoir structure is stable. Among them, deep mantle fluids are geological fluids originating from the Earth's deep mantle. They can migrate upwards along tectonic channels to the target oil and gas reservoir and mix with the primary strata fluids, thus forming the target geological fluids together with the primary strata fluids.

[0036] In one embodiment, a low input ratio can be determined when the input ratio of mantle-source argon is less than 3%, a medium input ratio can be determined when the input ratio of mantle-source argon is greater than or equal to 3% and less than 10%, and a high input ratio can be determined when the input ratio of mantle-source argon is greater than or equal to 10%.

[0037] When the input ratio of mantle-source argon is low, the target geological fluid in the target oil and gas reservoir area is almost completely mixed with deep mantle fluid from the mantle, and the whole is in a nearly static state; the stratigraphic structure and closed traps of the oil and gas reservoir are intact, and there is no disturbance from tectonic movement or external fluids, so the oil and gas storage conditions are stable.

[0038] Step S1802: When the input ratio of mantle-source argon is greater than or equal to 3% and less than 10%, it is determined that the target geological fluid is in a weakly active state and the oil and gas reservoir is slightly disturbed. When the input ratio of mantle-source argon is moderate, a certain amount of deep mantle fluid migrates upward and mixes into the target oil and gas reservoir, resulting in small-scale, localized fluid flow. The overall structure of the oil and gas reservoir is not damaged, only subjected to minor impacts, and its storage status is basically unaffected.

[0039] Step S1803: If the input ratio of mantle-source argon is greater than or equal to 10%, it is determined that the target geological fluid activity is strong and the oil and gas reservoir is significantly affected by deep mantle fluids.

[0040] When the input ratio of mantle-source argon is high, a large amount of deep mantle fluid flows into the target oil and gas reservoir, and the overall fluid flow is active. The strong deep mantle fluid and the accompanying tectonic activity significantly change the original environment of the oil and gas reservoir, which will affect the trap sealing and oil and gas preservation conditions.

[0041] In the above embodiments, three levels—low, medium, and high—are defined based on the proportion of mantle-source argon input. A direct correspondence is established between the proportion threshold and the characteristics of geological fluid activity and the state of oil and gas reservoirs. The classification criteria are clear and the judgment logic is intuitive. This allows for the rapid determination of the structural stability of oil and gas reservoirs, the degree of disturbance, and the intensity of the influence of deep mantle fluids. It avoids complex interpretation processes, and the results are intuitive and reliable. This provides a direct and effective decision-making basis for oil and gas exploration evaluation, development deployment, and safety assessment.

[0042] In some embodiments, the proportion of mantle-derived argon input in 89 geological fluid samples, including 82 natural gas samples collected from 10 natural gas fields in the Songliao Basin, Tarim Basin, Sichuan Basin, and Qaidam Basin in my country, and 7 hot spring gas samples collected from the eastern edge of the Qinghai-Tibet Plateau, was calculated.

[0043] Figure 2 This invention demonstrates 89 target geological fluid samples obtained using steps S110 to S150 of a method for determining the characteristics of mantle-derived argon input in geological fluids and the state of hydrocarbon reservoirs, as described in embodiments of this application. 40 Ar / 36 Measured ratio of Ar 40 Ar / 36 Theoretical ratios of Ar and geological time; such as Figure 2 As shown, the horizontal axis represents geological time (Ma, millions of years), and the vertical axis represents... 40 Ar / 36 The measured ratio of Ar ( The bottom horizontal line represents atmospheric argon. 40 Ar and 36 The fixed ratio of Ar is 295.5, and the top horizontal line represents the mantle end-member argon. 40 Ar and 36 The fixed ratio of Ar is approximately 15000.

[0044] Figure 2 The lower middle slant line is the excess argon coefficient line, and any point on this line satisfies... = The upper slant line is the excess argon coefficient double line. Any point on this line satisfies... = ×2, the area below the lower slant line indicates that the excess argon coefficient is less than 1, and there is no mantle-source argon mixed in at this time. The area between the two slant lines indicates that the excess argon coefficient is greater than or equal to 1 and less than or equal to 2, and there is suspected mantle-source argon mixed in at this time. The area above the upper slant line indicates that the excess argon coefficient is greater than 2, and there is confirmed mantle-source argon mixed in at this time.

[0045] Taking the Songliao Basin, the Anyue Gas Field in the Sichuan Basin, and the Jinqiu Gas Field in the Sichuan Basin as examples, most of the gas fields in the Songliao Basin are located in... Regions with a value greater than 2 indicate that these samples definitely have mantle-sourced argon input and strong deep mantle fluid activity; most points in the Anyue Gas Field and Jinqiu Gas Field in the Sichuan Basin are close to or below the excess argon coefficient line of 1, indicating that these samples have no obvious mantle-sourced argon input.

[0046] Figure 3 The study presented the mantle-source argon input ratio of target geological fluids with an excess argon coefficient Ex(Ar) > 1 calculated using step S170. The results showed that the mantle-source argon input ratio of these target geological fluids ranged from 0.03% to 49.95%. According to the classification standard, there were 22 samples in this study with a mantle-source argon input ratio of less than 3% (low input ratio) and greater than or equal to 3% but less than 10% (medium input ratio). Only 5 samples had a mantle-source argon input ratio greater than or equal to 10%, which is a high input ratio. Therefore, it was determined that the fluid activity in most areas of the region was limited and the overall state of the oil and gas reservoirs was stable.

[0047] Based on the foregoing embodiments, this application provides a system for determining the characteristics of mantle-derived argon input and the state of oil and gas reservoirs in geological fluids. The system includes various modules, sub-modules, and units, which can be implemented by a processor in an electronic device; or by specific logic circuits. In implementation, the processor can be a central processing unit (CPU), microprocessor (MPU), digital signal processor (DSP), or field programmable gate array (FPGA), etc.

[0048] Figure 4 A schematic diagram of the composition structure of a system for determining the characteristics of mantle-derived argon input in geological fluids and the state of hydrocarbon reservoirs, provided in an embodiment of this application, is shown below. Figure 4 As shown, the system 400 includes: Acquisition module 41 is used to collect target geological fluid samples from the target oil and gas reservoir area; Detection module 42 is used to detect the gaseous argon isotope composition in the target geological fluid sample using a rare gas mass spectrometer; The first determining module 43 is used to determine the mixed argon content in the target geological fluid sample based on the gaseous argon isotope composition. 40 Ar and 36 The measured ratio of Ar, wherein the mixed argon includes atmospheric argon, radiogenic argon and mantle-derived argon; The second determining module 44 is used to determine the geological time experienced by the source stratum based on the age of the source stratum of the target geological fluid sample. The first calculation module 45 is used to calculate the background argon in the source strata based on the geological time. 40 Ar and 36 The theoretical ratio of Ar, wherein the background argon of the formation includes atmospheric argon and radiogenic argon; The third determining module 46 is used to determine the excess argon coefficient based on the measured ratio and the theoretical ratio; The second calculation module 47 is used to, when the excess argon coefficient is greater than or equal to a preset threshold, calculate based on the measured ratio, the theoretical ratio, and the mantle end-member argon... 40 Ar and 36 The standard ratio of Ar is used to calculate the input proportion of mantle-derived argon in the target geological fluid sample; The fourth determining module 48 is used to determine the activity characteristics of the target geological fluid and the state of the oil and gas reservoir within the target oil and gas reservoir area based on the input ratio of the mantle-sourced argon.

[0049] In some possible embodiments, the first calculation module 45 is used to calculate the background argon in the source strata using the following formula. 40 Ar and 36 Theoretical ratio of Ar: ; in, 40 Ar is an isotope of argon-40. 36 Ar is an isotope of argon-36. The theoretical ratio is given, and T is the geological time.

[0050] In some possible embodiments, the third determining module 46 is used to calculate and determine the excess argon coefficient using the following formula: ; in, The measured ratio is... This is the excess argon coefficient.

[0051] In some possible embodiments, the second calculation module 47 is used to calculate the input proportion of mantle-derived argon in the target geological fluid sample using the following formula:

[0052] in, The input ratio of mantle-sourced argon. Argon for the mantle endmember 40 Ar and 36 The standard ratio of Ar.

[0053] In some possible embodiments, the target geological fluid includes primary stratigraphic fluid and deep mantle fluid, wherein the deep mantle fluid upwells along tectonic channels and mixes with the primary stratigraphic fluid, and the fourth determining module 48 includes: The first determination submodule is used to determine that the target geological fluid activity in the target oil and gas reservoir area is weak and the oil and gas reservoir structure is stable when the input ratio of mantle-source argon is less than 3%. The second determination submodule is used to determine that the target geological fluid is in a weakly active state and the oil and gas reservoir is slightly disturbed when the input ratio of the mantle-sourced argon is greater than or equal to 3% and less than 10%. The third determination submodule is used to determine, when the input ratio of mantle-source argon is greater than or equal to 10%, that the target geological fluid activity is strong and the oil and gas reservoir is significantly affected by deep mantle fluids.

[0054] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this application, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the above-described embodiments are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0055] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0056] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0057] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected to achieve the purpose of the embodiments of this application according to actual needs. In addition, each functional unit in the embodiments of this application may be fully integrated into one processing unit, or each unit may be a separate unit, or two or more units may be integrated into one unit; the integrated unit may be implemented in hardware or in the form of hardware plus software functional units.

[0058] Alternatively, if the integrated units described above are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, or the parts that contribute to related technologies, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause the device automatic test line to execute all or part of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0059] The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined to obtain new method embodiments without conflict. The features disclosed in the several method or device embodiments provided in this application can be arbitrarily combined to obtain new method embodiments or device embodiments without conflict.

[0060] The above description is merely an embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for determining the characteristics of mantle-derived argon input in geological fluids and the state of hydrocarbon reservoirs, characterized in that, The method includes: Collect target geological fluid samples from the target oil and gas reservoir area; The gaseous argon isotope composition in the target geological fluid sample was detected using a rare gas mass spectrometer. Based on the gaseous argon isotope composition, the mixed argon content in the target geological fluid sample was determined. 40 Ar and 36 The measured ratio of Ar, wherein the mixed argon includes atmospheric argon, radiogenic argon and mantle-derived argon; Based on the age of the source strata of the target geological fluid sample, determine the geological time experienced by the source strata; Based on the geological time, calculate the background argon in the source strata. 40 Ar and 36 The theoretical ratio of Ar, wherein the background argon of the formation includes atmospheric argon and radiogenic argon; The excess argon coefficient is determined based on the measured ratio and the theoretical ratio. When the excess argon coefficient is greater than or equal to a preset threshold, based on the measured ratio, the theoretical ratio, and the mantle end-member argon... 40 Ar and 36 The standard ratio of Ar is used to calculate the input proportion of mantle-derived argon in the target geological fluid sample; Based on the input ratio of mantle-sourced argon, the activity characteristics of the target geological fluid and the state of the oil and gas reservoir within the target oil and gas reservoir area are determined.

2. The method according to claim 1, characterized in that, The background argon in the source strata is calculated using the following formula. 40 Ar and 36 Theoretical ratio of Ar: ； in, 40 Ar is an isotope of argon-40. 36 Ar is an isotope of argon-36. The theoretical ratio is given, and T is the geological time.

3. The method according to claim 1, characterized in that, The excess argon coefficient is determined using the following formula: ； in, The measured ratio is... This is the excess argon coefficient.

4. The method according to claim 1, characterized in that, The input ratio of mantle-derived argon in the target geological fluid sample is calculated using the following formula: ； in, The input ratio of mantle-sourced argon. Argon for the mantle endmember 40 Ar and 36 The standard ratio of Ar.

5. The method according to claim 1, characterized in that, The target geological fluids include primary formation fluids and deep mantle fluids. The deep mantle fluids upwell along tectonic channels and mix with the primary formation fluids. Based on the input ratio of mantle-derived argon, the activity characteristics of the target geological fluids and the reservoir status within the target oil and gas reservoir area are determined, including: When the input ratio of mantle-sourced argon is less than 3%, it is determined that the target geological fluid activity in the target oil and gas reservoir area is weak and the oil and gas reservoir structure is stable. When the input ratio of mantle-source argon is greater than or equal to 3% and less than 10%, it is determined that the target geological fluid is in a weakly active state and the oil and gas reservoir is slightly disturbed. When the input ratio of mantle-source argon is greater than or equal to 10%, it is determined that the target geological fluid activity is strong and the oil and gas reservoir is significantly affected by deep mantle fluids.

6. A system for determining the characteristics of mantle-derived argon input in geological fluids and the state of hydrocarbon reservoirs, characterized in that, The system includes: The acquisition module is used to collect target geological fluid samples from the target oil and gas reservoir area; The detection module is used to detect the gaseous argon isotope composition in the target geological fluid sample using a rare gas mass spectrometer. The first determining module is used to determine the mixed argon content in the target geological fluid sample based on the gaseous argon isotope composition. 40 Ar and 36 The measured ratio of Ar, wherein the mixed argon includes atmospheric argon, radiogenic argon and mantle-derived argon; The second determining module is used to determine the geological time experienced by the source stratum based on the age of the source stratum of the target geological fluid sample. The first calculation module is used to calculate the background argon in the source strata based on the geological time. 40 Ar and 36 The theoretical ratio of Ar, wherein the background argon of the formation includes atmospheric argon and radiogenic argon; The third determining module is used to determine the excess argon coefficient based on the measured ratio and the theoretical ratio; The second calculation module is used to, when the excess argon coefficient is greater than or equal to a preset threshold, calculate based on the measured ratio, the theoretical ratio, and the mantle end-member argon. 40 Ar and 36 The standard ratio of Ar is used to calculate the input proportion of mantle-derived argon in the target geological fluid sample; The fourth determination module is used to determine the activity characteristics of the target geological fluid and the state of the oil and gas reservoir within the target oil and gas reservoir area based on the input ratio of the mantle-sourced argon.

7. The system according to claim 6, characterized in that, The target geological fluid includes primary stratigraphic fluid and deep mantle fluid. The deep mantle fluid flows up along tectonic channels and mixes with the primary stratigraphic fluid. The fourth determining module includes: The first determination submodule is used to determine that the target geological fluid activity in the target oil and gas reservoir area is weak and the oil and gas reservoir structure is stable when the input ratio of mantle-source argon is less than 3%. The second determination submodule is used to determine that the target geological fluid is in a weakly active state and the oil and gas reservoir is slightly disturbed when the input ratio of the mantle-sourced argon is greater than or equal to 3% and less than 10%. The third determination submodule is used to determine, when the input ratio of mantle-source argon is greater than or equal to 10%, that the target geological fluid activity is strong and the oil and gas reservoir is significantly affected by deep mantle fluids.

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