A method for analyzing sandbody architecture in tight gas reservoirs based on multi-information fusion

Abstract

The present invention provides a method for analyzing the sand body configuration of tight gas reservoirs based on multi-information fusion, including step 1. dividing the river channel stages based on the similarity of well logging curve morphology, physical properties and seismic attribute differences, and clarifying how many sets of single sand bodies are developed in each river channel stage. Step 2. Based on sedimentary microfacies, different levels of configuration units are divided. Step 3. Based on the vertical combination of configuration units, the configuration unit combination is divided into 5 categories, including beach + beach, beach + river channel filling deposition, river channel filling deposition + estuary dam, river channel filling deposition + breach fan + natural levee + abandoned river channel, and river channel filling deposition + river channel filling deposition. On the basis of existing research, the present invention comprehensively considers the vertical combination of configuration units, the lithofacies and combinations of single sand bodies, rhythmic structures, the sand-mud combination types and characteristic differences developed inside the sand group, and the sand body superposition style, and comprehensively evaluates the configuration into three categories.

Description

Technical Field

[0001] The present invention belongs to the technical field of geological analysis, and particularly relates to a method for analyzing the sand body configuration of tight gas reservoirs based on multi-information fusion. Background Art

[0002] Tight sandstone gas, as an unconventional gas reservoir, has great resource prospects worldwide. The total reserves and annual total output of tight sandstone gas fields in China have respectively accounted for about 1 / 3 and 1 / 4 of the total reserves and annual total output of natural gas in China, and have become the most important and realistic source for replacing conventional oil and gas resources in the next one or two decades. The large tight gas fields in China are mainly distributed in the Ordos Basin, Sichuan Basin and Tarim Basin, mainly in the Carboniferous, Permian, Triassic, Jurassic, Cretaceous and Paleogene-Neogene. Tight gas reservoirs have the geological characteristics of quasi-continuous accumulation and near-source efficient reservoir formation. China has rich resources of low-permeability gas reservoirs, large proven reserve scale and strong development potential. The physical properties of tight sandstone reservoirs in China are poor, with strong heterogeneity, thin thickness, poor continuity and complex later tectonics. Therefore, the exploration work of tight gas in China is difficult, and a comprehensive evaluation method and exploitation technology for the characteristics of tight gas in China need to be formed.

[0003] Previous studies have carried out a large amount of research work on sand body configuration. However, previous studies basically adopted the traditional configuration research idea to carry out relevant research, mainly based on sedimentary microfacies, dividing different-level single sand body configuration units, and analyzing the scale, shape, direction and their superimposed relationship of the configuration units. At present, the existing problems are specifically reflected in the following aspects: First, the scale of high-yield areas in the study area is relatively limited, and the single-well production and reserves of the same set of channel sand bodies vary greatly. Second, the physical properties and gas-bearing properties of sandstones with different lithofacies are quite different. Third, the channel type and its connectivity have a great influence on the physical properties and gas-bearing properties of sandstones.

[0004] The present invention mainly adopts a new set of configuration analysis methods to carry out research on reservoir heterogeneity, so as to analyze and clarify the above series of problems existing in the production and development of the study area. The results of this study not only have strong practical significance for the exploration and development of natural gas in tight sandstone reservoirs, but also provide a theoretical basis for the prediction of high-quality reservoirs.

[0005] Technical Solution of the Existing Technology I

[0006] A method for quantitative analysis of sand body configuration. CN201910793343.0

[0007] This technology mainly identifies the cycle interfaces in the study area; determines the sandbody configuration interfaces based on the cycle interfaces; analyzes the sandbody configuration interfaces to obtain the single-well sandbody configuration elements and contact relationships; combines the single-well sandbody configuration elements and contact relationships to obtain the longitudinal sandbody splicing relationships; predicts the lateral sandbody splicing relationships based on the longitudinal sandbody splicing relationships; obtains the sandbody plane distribution map based on the longitudinal sandbody splicing relationships and the lateral sandbody splicing relationships; and uses Monte Carlo simulation based on the sandbody plane distribution map to achieve fine characterization of the sandbody shape and scale.

[0008] Disadvantages of the prior art I

[0009] This technical method uses traditional configuration research ideas to carry out relevant research. It mainly divides different-level single-sandbody configuration units based on sedimentary microfacies and analyzes the scale, shape, direction, and stacking relationship of the configuration units.

[0010] Technical solution of the prior art II

[0011] A method for characterizing the configuration of a single sandbody in a clastic reservoir. CN202010927034.0

[0012] Establish a vertical configuration model of a single sandbody corresponding to core characteristics; establish a vertical configuration model of a single sandbody corresponding to the corresponding characteristics of logging curves; then, through feature matching of the rock-electric relationship, use the attribute clustering analysis method to establish a vertical configuration model of a single sandbody corresponding to core characteristics and the corresponding characteristics of logging curves, and use this model to interpret the configuration model of a single sandbody vertically in a non-cored single well; further clarify the lateral configuration model of a single sandbody; and combine the reservoir configuration theory to complete the quantitative characterization of the single sandbody configuration.

[0013] Disadvantages of the prior art II

[0014] This technical method uses traditional configuration research ideas to carry out relevant research. It mainly divides different-level single-sandbody configuration units based on sedimentary microfacies and analyzes the scale, shape, direction, and stacking relationship of the configuration units.

[0015] Technical solution of the prior art II

[0016] A method for predicting the configuration of sandbodies in a fluvial delta facies. CN202020992499.4

[0017] Obtain the gamma-ray detection response curves of each individual well at the target depth interval; based on the gamma-ray detection response curves, statistically calculate the sand body thickness of each individual well at the target depth interval, and draw a planar map of the sand body thickness distribution; distinguish box-shaped curves and bell-shaped curves from the gamma-ray detection response curves according to their shapes; mark the box-shaped curves and bell-shaped curves distinguished from the gamma-ray detection response curves beside the corresponding well positions in the isopach map of the sand body thickness, and circle the box-shaped area corresponding to the box-shaped curve and the bell-shaped area corresponding to the bell-shaped curve in the map.

[0018] Disadvantages of the prior art three

[0019] This technical method mainly relies on well logging curves for prediction, with low credibility. Summary of the invention

[0020] The purpose of the present invention is to solve the defects existing in the above-mentioned prior art, and provide a method for analyzing the sand body architecture of tight gas reservoirs based on multi-information fusion. On the basis of existing research, the present invention comprehensively considers the vertical combination of architecture units, the lithofacies and their combinations in which single sand bodies develop, the rhythm structure, the types and characteristic differences of sand-mud combinations developed within sand groups, the sand body stacking patterns, etc., and comprehensively evaluates the architecture into three categories.

[0021] A large amount of research work has been carried out on sand body architecture in the prior art, but the existing research in the prior art basically adopts the traditional research idea of architecture to carry out relevant research, mainly based on sedimentary microfacies, dividing architecture units of different orders of single sand bodies, and analyzing the scale, shape, direction and their stacking relationships of architecture units. With the continuous advancement of the exploration and development of tight gas reservoirs, the current traditional research idea of architecture cannot meet the needs of the current exploration and development of tight gas reservoirs. In this study, the sand body architecture is mainly based on the research of architecture units of different orders divided by sedimentary microfacies, and comprehensively considers the vertical combination of architecture units of different orders, the lithofacies and their combinations in which single sand bodies develop, the rhythm structure, the types and characteristic differences of sand-mud combinations developed within sand groups, the sand body stacking patterns, etc., and comprehensively evaluates the architecture into three categories.

[0022] The present invention adopts the following technical solutions:

[0023] A method for analyzing the sand body architecture of tight gas reservoirs based on multi-information fusion, comprising

[0024] Step 1. Based on the similarity of well logging curve shapes, physical properties and seismic attribute differences, divide the river channel periods and clarify how many sets of single sand bodies are developed in each river channel period.

[0025] Step 2. Based on sedimentary microfacies, divide architecture units of different orders.

[0026] Through previous research, it is considered that the single sand bodies in the target sand group in the study area mainly develop 6 types of architecture units, such as point bars, channel fills, mouth bars, crevasse splays, natural levees, and abandoned channels.

[0027] Step 3. Based on the vertical combination of configuration units, the configuration unit combinations can be divided into 5 categories, including point bar + point bar, point bar + channel fill deposit, channel fill deposit + mouth bar, channel fill deposit + crevasse splay + natural levee + abandoned channel, and channel fill deposit + channel fill deposit.

[0028] Among them, the sand bodies with the combination of point bar + point bar have the best physical properties, with an average porosity of 12%-14% and an average permeability of 0.8-0.9 mD. The combinations of point bar + channel fill deposit and channel fill deposit + mouth bar are second, with an average porosity of 10%-12% and an average permeability of 0.5-0.6 mD.

[0029] Step 4. Through the study of the litho-electric characteristics of single sand bodies in the target sand group of the study area, a lithofacies combination type and rhythm structure type chart of single sand bodies was established.

[0030] Among them, the single sand bodies with the lithofacies combination of massive bedding and cross-bedding are mainly of uniform rhythm and positive rhythm, and have the best physical properties, with an average porosity of 12% and an average permeability of 0.934 mD.

[0031] The point bar and channel fill deposit develop uniform rhythm and positive rhythm respectively, and their physical properties are generally good, with an average porosity of 10%-14% and an average permeability of 0.727-0.847 mD. The mouth bar develops reverse rhythm and its physical properties are second, with an average porosity of 10% and an average permeability of 0.341 mD.

[0032] Thin sand bodies such as natural levees and crevasse splays develop composite rhythms; their physical properties are generally poor, with an average porosity of 7% and an average permeability of 0.041 mD.

[0033] Step 5. Based on the differences in physical properties and logging response characteristics, the lithofacies are classified into 3 categories: Type I homogeneous lithofacies, Type II weakly heterogeneous lithofacies, and Type III strongly heterogeneous lithofacies.

[0034] The sandstone developed in Type I homogeneous lithofacies has a large thickness, high porosity and permeability of the sand body, high daily gas production, and stable sand body distribution; the GR of the sandstone developed in Type I homogeneous lithofacies is relatively low (<69 API), the AC is relatively large (70-79 μs / ft), and the DEN is relatively small (2.32-2.48 g / cm 3 )

[0035] Combined with geological logging, the classification study of sand-mud combinations in each sand group was carried out, and it was clarified that there are mainly 3 types of sand-mud combinations developed in the target sand group of the study area, including: thick sand intercalated with thin silty mud (uniform type), medium-thick sand intercalated with thin mud (composite type ①), and thick mud intercalated with thin fine sand (composite type ②).

[0036] Among them, the sand bodies with thick sand interbedded with thin silty mud (homogeneous type) have the best physical properties, with an average porosity of 12%-14% and an average permeability of 0.8-0.9 mD.

[0037] Three types of sand body stacking patterns are divided, including scouring and cutting type, scouring contact type, and isolated type. Among them, the scouring and cutting type is mostly manifested as the superimposed distribution of multi-stage channel sand bodies, and high-quality reservoirs are developed.

[0038] Step 7. Based on the sand body stacking pattern, sand-mud combination, configuration unit combination, rhythm structure type and characteristics of lithofacies, etc., three types of configurations are divided, and a configuration evaluation model is established.

[0039] Among them, the sand bodies with Class I configuration are mainly of scouring and cutting type and contact type, the sand-mud combination is mainly thick sand interbedded with thin silty mud (homogeneous type), the bar + bar configuration unit combination is developed, and the Class I homogeneous lithofacies is developed in single sand bodies, which is beneficial to the development of high-quality reservoirs.

[0040] Advantages of the present invention:

[0041] The present invention proposes a set of analysis methods for sand body configuration of tight gas reservoirs based on multi-information fusion, which can more efficiently and accurately analyze the degree of heterogeneity of tight gas reservoir reservoirs, and clarify a series of the above problems existing in the production and development of the research area. The results of this study not only have strong practical significance for the exploration and development of natural gas in tight sandstone reservoirs, but also provide a theoretical basis for the prediction of high-quality reservoirs. It is of great significance for the gas field to "increase reserves and production", and at the same time solves the problem of the supply and demand of clean energy in China. Brief description of the drawings

[0042] Figure 1 is the analysis flow chart of the present invention;

[0043] Figure 2 is the lithofacies combination diagram of the typical well I profile;

[0044] Figure 3 is the lithofacies combination diagram of the typical well II profile;

[0045] Figure 4 is the lithofacies combination diagram of the typical well III profile;

[0046] Figure 5 is the rhythm structure diagram of the typical well I profile;

[0047] Figure 6 is the rhythm structure diagram of the typical well II profile;

[0048] Figure 7 is the rhythm structure diagram of the typical well III profile;

[0049] Figure 8 is the rhythm structure diagram of the typical well IV profile;

[0050] Figure 9 Configuration unit combination and sand-mud combination pattern diagram for the development of Class I configuration;

[0051] Figure 10 Configuration unit combination and sand-mud combination pattern diagram for the development of Class II configuration;

[0052] Figure 11 Configuration unit combination and sand-mud combination pattern diagram for the development of Class III configuration;

[0053] Figure 12 Typical cross-well profile example of Class I configuration and schematic diagram of developed lithofacies types;

[0054] Figure 13 Typical cross-well profile example of Class II configuration and schematic diagram of developed lithofacies types;

[0055] Figure 14 Typical cross-well profile example of Class III configuration and schematic diagram of developed lithofacies types;

[0056] Figure 15 Seismic attribute value range diagram of Class I configuration;

[0057] Figure 16 Seismic attribute value range diagram of Class II configuration;

[0058] Figure 17 Seismic attribute value range diagram of Class III configuration. Detailed implementation manners

[0059] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be described clearly and completely below. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without making creative efforts based on the embodiments in the present invention fall within the protection scope of the present invention.

[0060] Previous studies basically carried out relevant research by adopting the traditional configuration research idea, mainly based on sedimentary microfacies, dividing the configuration units of single sand bodies, and analyzing the scale, shape, direction and their superimposed relationships of configuration units at different levels. At present, the traditional configuration research idea cannot meet the requirements of the current exploration and development of tight gas reservoirs. With the continuous advancement of the exploration and development of tight gas reservoirs, the existing problems are specifically reflected in the following aspects: First, the scale of high-yield areas in the study area is relatively limited, and there are large differences in the single-well production and reserves of the same set of channel sand bodies. Second, there are large differences in the physical properties and gas-bearing properties of sandstones with different lithofacies. Third, the channel types and their connectivity have a great influence on the physical properties and gas-bearing properties of sandstones.

[0061] The present invention mainly adopts a new set of configuration analysis methods to carry out research related to reservoir heterogeneity, so as to analyze and clarify the above-mentioned series of problems existing in the production and development of the study area. The results of this study not only have strong practical significance for the exploration and development of natural gas in tight sandstone reservoirs, but also provide a theoretical basis for the prediction of high-quality reservoirs.

[0062] Example

[0063] As Figure 1 shown, taking the channel sandstones of the 6th, 7th, 8th, and 9th sand groups in the second sub-member of the second member of the Shahejie Formation in Jinqiu Gas Field as the research object, the sand body configuration research is carried out, and the specific research ideas are as Figure 1 shown. First of all, based on the similarity of logging curves, physical properties, and seismic attribute differences, the channel periods are divided to clarify how many sets of single sand bodies are developed in each channel. On this basis, different-level configuration units are divided based on sedimentary microfacies. Through previous research, it is considered that the single sand bodies in the target sand group of the study area mainly develop 6 types of configuration units, such as point bar, channel fill deposit, mouth bar, crevasse splay, natural levee, and abandoned channel.

[0064] Based on the vertical combination of configuration units, the configuration unit combinations can be divided into 5 types, including: point bar + point bar, point bar + channel fill deposit, channel fill deposit + mouth bar, channel fill deposit + crevasse splay + natural levee + abandoned channel, and channel fill deposit + channel fill deposit.

[0065] Among them, the sand bodies with point bar + point bar have the best physical properties, followed by point bar + channel fill deposit and channel fill deposit + mouth bar.

[0066] Through the study of the litho-electric characteristics of the single sand bodies in the target sand group of the study area, the lithofacies combination types and rhythm structure type plates of the single sand bodies are established, as Figures 2 - 4 and Figures 5 - 8 shown. Among them, the single sand bodies with massive bedding and cross-bedding lithofacies combinations are mainly characterized by uniform rhythm and positive rhythm, and have the best physical properties. Point bar and channel fill deposit develop uniform rhythm and positive rhythm respectively, and their physical properties are generally good; the mouth bar develops reverse rhythm and its physical properties are second; thin-layer sand bodies such as natural levee and crevasse splay develop composite rhythm, and their physical properties are generally poor.

[0067] As Figure 2 shown, in the typical well Ⅰ, small-scale cross-bedded fine-grained sandstone, large-scale cross-bedded medium-grained sandstone, and massive-bedded medium-grained sandstone can be observed in the core of this well. The lithofacies combination developed in this well is: massive-bedded sandstone facies + cross-bedded sandstone facies combination. The physical properties of this type of lithofacies combination are good. Among them, the average porosity is 13%, and the average permeability is 1.653 mD. Among them, the depth of the small-scale cross-bedded fine-grained sandstone is 2143.85 - 2144.11 m, the depth of the massive-bedded medium-grained sandstone is 2145.19 - 2145.30 m, and the depth of the large-scale cross-bedded medium-grained sandstone is 2157.19 - 2157.36 m.

[0068] As Figure 3 shown, for typical well Ⅱ, small-scale cross-bedded fine-grained sandstone and parallel-bedded medium-grained sandstone can be observed in the core of this well. The lithofacies combination developed in this well is: cross-bedded sandstone facies + parallel-bedded sandstone facies combination. The physical properties of this type of lithofacies combination are good. Among them, the average porosity is 10%, and the average permeability is 0.929 mD. The depth of the small-scale cross-bedded fine-grained sandstone is 2081.66 - 2081.95 m, the depth of the parallel-bedded medium-grained sandstone is 2089.32 - 2089.59 m, and the depth of the small-scale cross-bedded fine-grained sandstone is 2098.17 - 2098.30 m.

[0069] As Figure 4 shown, for typical well Ⅲ, small-scale cross-bedded fine-grained sandstone, parallel-bedded fine-grained sandstone, and horizontal-bedded argillaceous siltstone can be observed in the core of this well. The lithofacies combination developed in this well is: horizontal-bedded argillaceous siltstone facies combination. The physical properties of this type of lithofacies combination are poor. Among them, the average porosity is 8%, and the average permeability is 0.103 mD. The depth of the small-scale cross-bedded fine-grained sandstone is 2170.74 - 2170.89 m, the depth of the parallel-bedded fine-grained sandstone is 2171.65 - 2171.85 m, and the depth of the horizontal-bedded argillaceous siltstone is 2182.73 - 2182.99 m.

[0070] As Figure 5 shown, for typical well Ⅰ, large-scale cross-bedded medium-grained sandstone and massive-bedded medium-grained sandstone can be observed in the core of this well. This well develops a uniform rhythm structure, which belongs to a rhythm structure with good physical properties, and its average porosity is 14%, and the average permeability is 0.847 mD.

[0071] As Figure 6 shown, for typical well Ⅱ, large-scale cross-bedded medium-grained sandstone and small-scale cross-bedded fine-grained sandstone can be observed in the core of this well. This well develops a positive rhythm structure, which belongs to a rhythm structure with good physical properties, and its average porosity is 10%, and the average permeability is 0.727 mD.

[0072] As Figure 7 shown, for typical well Ⅲ, small-scale cross-bedded fine-grained sandstone can be observed in the core of this well. This well develops an inverse rhythm structure, which belongs to a rhythm structure with poor physical properties, and its average porosity is 10%, and the average permeability is 0.341 mD.

[0073] As Figure 8As shown in the figure, for the typical well Ⅳ, small-scale cross-bedded fine-grained sandstone can be observed in the core of this well. This well develops a composite rhythm, belonging to a rhythm structure with poor physical properties, with an average porosity of 7% and an average permeability of 0.041 mD. Based on the differences in physical properties and logging response characteristics, the lithofacies are classified into 3 major categories: Type I homogeneous lithofacies, Type II weakly heterogeneous lithofacies, and Type III strongly heterogeneous lithofacies. The sandstone developed in Type I homogeneous lithofacies has a large thickness, high porosity and permeability of the sand body, high daily gas production, and stable distribution of the sand body; the GR of the well developed with Type I homogeneous lithofacies is relatively low, the AC is relatively large, and the DEN is relatively small.

[0074] Combined with geological logging, classification research on various sand-mud combinations has been carried out, and it is clear that there are mainly 3 types of sand-mud combinations developed in the target sand groups in the study area, including: thick sand interbedded with thin silty mud (homogeneous type), medium-thick sand interbedded with thin mud (composite ① type), and thick mud interbedded with thin fine sand (composite ② type). Among them, the sand body developed with thick sand interbedded with thin silty mud (homogeneous type) has the best physical properties. Three types of sand body stacking patterns are divided, including: scouring and cutting type, scouring and contact type, and isolated type. Among them, the scouring and cutting type mostly shows the superimposed distribution of multi-stage channel sand bodies, and high-quality reservoirs are developed.

[0075] Based on the sand body stacking pattern, sand-mud combination, configuration unit combination, rhythm structure type and characteristics of lithofacies, etc., three types of configurations are divided, and a configuration evaluation model is established, as Figures 9 - 2 shown in Figure 0. Among them, the sand bodies developed with Type I configuration are mainly of scouring and cutting type and contact type, the sand-mud combination is mainly thick sand interbedded with thin silty mud (homogeneous type), the configuration unit combination of point bar + point bar is developed, and Type I homogeneous lithofacies is developed in single sand bodies, which is beneficial to the development of high-quality reservoirs.

[0076] As Figures 9 - 11 shown, the configuration unit combinations and sand-mud combinations developed in different configuration types. Among them, Type#I configuration mainly develops the configuration unit combination of point bar + point bar and develops homogeneous sand-mud combination; Type#II configuration mainly develops the configuration unit combinations of channel + point bar and channel + mouth bar and develops composite ① type sand-mud combination; Type#III configuration mainly develops the configuration unit combinations of channel + channel and channel + crevasse splay + natural levee + abandoned channel and develops composite ② type sand-mud combination.

[0077] As Figures 12 - 14 shown, Type#I configuration mainly develops Type I homogeneous lithofacies and is developed in connected channels, such as the AA' section in the figure; Type#II configuration mainly develops Type II weakly heterogeneous lithofacies and is developed in locally connected channels, as shown in the BB' section in the figure; Type#III configuration mainly develops Type III strongly heterogeneous lithofacies and is developed in channels with poor connectivity, as shown in the CC' section in the figure.

[0078] As Figures 15 - 17As shown, they are the seismic attribute value ranges of the Type#I configuration, RMS value: >6250; the seismic attribute value ranges of the Type#II configuration, RMS value: 5250 - 6250; the seismic attribute value ranges of the Type#III configuration, RMS value: <5250.

[0079] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for analyzing sand body configuration in tight gas reservoirs based on multi-information fusion, characterized in that , including: Step 1. Based on the similarity of logging curve morphology, physical properties, and seismic attribute differences, divide the river channel periods and clarify how many sets of single sand bodies are developed in each river channel period; Step 2. Based on sedimentary microfacies, divide different levels of configuration units; Step 3. Based on the vertical combination of configuration units, divide the configuration unit combinations into 5 categories, including point bar + point bar, point bar + channel fill deposit, channel fill deposit + mouth bar, channel fill deposit + crevasse splay + natural levee + abandoned channel, channel fill deposit + channel fill deposit; Step 4. Through the study of the litho-electric characteristics of single sand bodies in the target sand group in the study area, establish the lithofacies combination types and rhythm structure type plates of single sand bodies; Step 5. Based on the differences in physical properties and logging response characteristics, classify the lithofacies into 3 major categories: Type I homogeneous lithofacies, Type II weakly heterogeneous lithofacies, and Type III strongly heterogeneous lithofacies; Step 6. Combining geology and logging, conduct a classification study on the sand-mud combinations of each sand group, clarify the target sand groups in the study area, and mainly develop 3 types of sand-mud combinations, including: thick sand intercalated with thin silty mud, medium-thick sand intercalated with thin mud, thick mud intercalated with thin fine sand; divide 3 types of sand body stacking patterns, including scouring and cutting type, scouring contact type, and isolated type; Step 7. Based on the sand body stacking pattern, sand-mud combination, configuration unit combination, and the rhythm structure types and characteristics of lithofacies, divide into three types of configurations and establish a configuration analysis model; The sand bodies developed with Type I configuration are mainly of scouring and cutting type and contact type, the sand-mud combination is mainly thick sand intercalated with thin silty mud, the configuration unit combination of point bar + point bar is developed, and Type I homogeneous lithofacies are developed in single sand bodies, which is conducive to the development of high-quality reservoirs; Type II configuration mainly develops the configuration unit combinations of channel + point bar and channel + mouth bar, develops the sand-mud combination of medium-thick sand intercalated with thin mud, and mainly develops Type II weakly heterogeneous lithofacies; Type III configuration mainly develops the configuration unit combinations of channel + channel and channel + crevasse splay + natural levee + abandoned channel, develops the sand-mud combination of thick mud intercalated with thin fine sand, and mainly develops Type III strongly heterogeneous lithofacies.

2. The method for analyzing sandbody architecture of tight gas reservoirs based on multi-information fusion according to claim 1, wherein , in Step 2, the single sand bodies in the target sand group in the study area mainly develop 6 types of configuration units, including point bar, channel fill deposit, mouth bar, crevasse splay, natural levee, and abandoned channel.

3. The method for analyzing the sandbody configuration of a tight gas reservoir based on multi-information fusion according to claim 1, wherein , in Step 3, the average porosity of the sand bodies developed with point bar + point bar is 12% - 14%, and the average permeability is 0.8 - 0.9 mD. The average porosity of the sand bodies of point bar + channel fill deposit and channel fill deposit + mouth bar is 10% - 12%, and the average permeability is 0.5 - 0.6 mD.

4. The method for analyzing the sand body configuration of a tight gas reservoir based on multi-information fusion according to claim 1, wherein , in Step 4, the single sand bodies developed with the lithofacies combination of massive bedding and cross-bedding are mainly of uniform rhythm and positive rhythm, with an average porosity of 12% and an average permeability of 0.934 mD; the point bar and channel fill deposit develop uniform rhythm and positive rhythm respectively, with an average porosity of 10% - 14% and an average permeability of 0.727 mD - 0.847 mD; the mouth bar develops reverse rhythm, with an average porosity of 10% and an average permeability of 0.341 mD; the thin-layer sand bodies of natural levee and crevasse splay develop composite rhythm, with an average porosity of 7% and an average permeability of 0.041 mD.

5. The method for analyzing the sand body configuration of a tight gas reservoir based on multi-information fusion according to claim 1, wherein , in Step 5, the sandstone with the development of Class I homogeneous lithofacies has a large thickness, high porosity and permeability of the sand body, high daily gas production, and stable distribution of the sand body; GR < 69 API, AC is 70 - 79 us / ft, and DEN is 2.32 - 2.48 g / cm for the sand body with the development of Class I homogeneous lithofacies 3 .

6. The method for analyzing the sand body configuration of a tight gas reservoir based on multi-information fusion according to claim 1, wherein , In step 6, the average porosity of the sand body with thick sand intercalated with thin silty mud is 12%-14%, and the average permeability is 0.8-0.9 mD; the scouring and cutting type mostly shows the superimposed distribution of multi-stage channel sand bodies, and high-quality reservoirs are developed.

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