Connectivity verification method of channel sand bodies in tight gas reservoirs based on dynamic and static information fusion

Abstract

The present invention provides a method for verifying the connectivity of a channel sand body in a tight gas reservoir based on dynamic and static information fusion, comprising the following steps: step 1: determining the sand body superposition pattern of the channel sand body; step 2: determining the vertical configuration combination type of the channel sand body; step 3: determining the sand-mud combination type of different sand body configurations of the channel sand body; step 4: determining the configuration unit combination type of the channel sand body; step 5: determining the lithofacies of the channel sand body; step 6: combining with seismic attribute analysis; step 7: determining the sand body connectivity of the channel sand body according to the parameters of the channel sand body in step 1-6; step 8: combining with dynamic data verification of a production well; the channel sand body connectivity verification is carried out by fusion of dynamic and static information, so as to efficiently and accurately evaluate the strength of reservoir heterogeneity, and provide a sufficient theoretical basis for the production and development of tight gas reservoirs in my country.

Description

Technical Field

[0001] The invention belongs to the technical field of geological analysis, and in particular relates to a method for verifying the connectivity of a tight gas reservoir channel sand body based on dynamic and static information fusion. Background Art

[0002] As an unconventional gas reservoir, tight sandstone gas has huge resource prospects worldwide. The total reserves and annual total production of tight sandstone gas fields in China account for about 1 / 3 and 1 / 4 of China's total natural gas reserves and annual total production, respectively, and have become the most important and realistic source of conventional oil and gas resources in the next 10 to 20 years. my country's large tight gas fields are mainly distributed in the Ordos Basin, Sichuan Basin and Tarim Basin, mainly located 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 accumulation. my country has rich low-permeability gas reservoirs, large proven reserves and strong development potential. my country's tight sandstone reservoirs have poor physical properties, strong heterogeneity, thin thickness, poor continuity and complex later structures. Therefore, China's tight gas exploration is difficult, and it is necessary to form a comprehensive evaluation method and mining technology for China's tight gas characteristics.

[0003] The connectivity of river sand bodies is one of the important factors affecting oil and gas production and development. In the process of oil and gas field production and development, well network deployment and development methods need to be based on the analysis of river sand body connectivity. The river sand bodies in my country's large-scale tight gas fields are often complex in distribution, with multiple periods of river sand bodies superimposed and developed, and the reservoir heterogeneity is strong, which makes the connectivity of river sand bodies in each period very complex, increasing the difficulty of predicting river sand body connectivity.

[0004] 1. Technical solution of prior art 1:

[0005] Inter-well sand body static connectivity evaluation method based on sedimentary environment and evaluation scale. CN202111471432.7, the present invention relates to an inter-well sand body static connectivity evaluation method based on sedimentary environment and evaluation scale, which includes: identifying and dividing a single sand body conducting layer; taking the formation sand-to-ground ratio, sedimentary environment, evaluation scale, and sand body geometric parameters as the main controlling factors for conducting layer evaluation, taking one of the main evaluation factors as the object, and using the factor control method to clarify the control effect of the other three main evaluation factors on the static connectivity of the conducting layer; establishing a three-dimensional static connectivity model of a single sand body conducting layer, using petrel geological modeling software to achieve modeling, and achieving quantitative output; quantitatively distinguishing the closure type based on the static connectivity of the sand body.

[0006] Disadvantages of prior art 1:

[0007] This technology only considers the static perspective and realizes the quantitative evaluation of static connectivity of sand bodies of different genetic types based on the sedimentary environment and evaluation scale parameters, but does not carry out sand body connectivity evaluation in combination with dynamic data.

[0008] 2. Technical solution of the second prior art:

[0009] A method and device for determining sand body connectivity. CN201810042852.5. This technology mainly determines the reservoir type of the target layer segment at the drilling position of the injection and production well based on the logging data and the core sample analysis data; based on the reservoir type, determines the sand body connectivity along the target layer segment between the injection well and the production well in the injection and production well.

[0010] Disadvantages of the second prior art:

[0011] This technical method is mainly based on well logging and core data, and determines the reservoir type to evaluate the difference in sand body connectivity between the injection well and the production well along the target layer. This technical method considers relatively single factors, is limited to qualitative evaluation, and the credibility of the evaluation results is low.

[0012] 3. Technical solution of prior art 3:

[0013] A method and device for determining sand body connectivity. CN201711257300.8, the method provides first geological parameter information of a first single sand body and second geological parameter information of a second single sand body in a target work area, as well as standard indicators corresponding to a plurality of specified connectivity levels; the method comprises: respectively determining the membership relationship between each standard indicator and each specified connectivity level; setting a weight matrix corresponding to the standard indicator according to the standard indicator, and respectively determining the target weight value of each standard indicator in the weight matrix; determining the target indicator and the target indicator parameter value according to the first geological parameter information and the second geological parameter information, and determining the sand body connectivity between the first single sand body and the second single sand body according to the target indicator parameter value, the target weight value of the standard indicator and the membership relationship.

[0014] Disadvantages of the prior art three:

[0015] This technical method mainly determines the target index and the target index parameter value based on the first geological parameter information and the second geological parameter information, and determines the difference in sand body connectivity between the first single sand body and the second single sand body based on the target index parameter value, the target weight value of the standard index and the membership relationship. This technical method mainly determines the vertical connectivity of the sand body by comparing the difference in geological parameters between the two sets of single sand bodies, and the difference in the lateral connectivity of the river channel sand body is still unclear. Summary of the invention

[0016] In order to solve the defects in the prior art, the present invention provides a method for verifying the connectivity of river channel sand bodies in tight gas reservoirs based on dynamic and static information fusion. After evaluating the connectivity level of the river channel sand bodies, the connectivity verification of the river channel sand bodies is carried out by combining the seismic attribute differences and dynamic data analysis through dynamic and static information fusion, thereby efficiently and accurately evaluating the strength of reservoir heterogeneity, providing sufficient theoretical basis for the production and development of tight gas reservoirs in my country.

[0017] The method for verifying the connectivity of channel sand bodies in tight gas reservoirs based on dynamic and static information fusion includes the following steps:

[0018] Step 1: Determine the sand body superposition pattern of the channel sand body.

[0019] Combined with geological logging, a classification study on the superposition styles of sand bodies in each sand group was carried out, and three types of sand body superposition styles were divided, including scour-cutting type, scour-contact type, and isolated type.

[0020] The scour-cut sand body superposition style is formed under stable and strong hydrodynamic conditions. The early river channel is scour-cut by the late river channel, which is often manifested as the superimposed distribution of multi-stage river channel sand bodies and the development of high-quality reservoirs.

[0021] The scour contact sand body superposition style is easily formed under the condition of frequent changes in hydrodynamic conditions, and the mudstone thickness is relatively large.

[0022] The isolated sand body superposition style is easily formed under the conditions of frequent migration and diversion of the river channel, and the mudstone thickness is large.

[0023] Step 2: Determine the vertical configuration combination type of the channel sand body.

[0024] Based on the sand body superposition style and sand-mud combination, architectural unit combination, lithofacies and rhythmic structure type and characteristics, three types of architecture are divided.

[0025] The sand bodies with Type I architecture are mainly scour-cutting type and contact type, the sand-mud combination is mainly thick sand intercalated with thin silty mud (homogeneous type (HT type)), the beach + beach architecture unit combination is well developed, and Type I homogeneous lithofacies is developed in single sand bodies, which is conducive to the development of high-quality reservoirs.

[0026] The sand bodies with type II architecture are mainly contact type, the sand-mud combination is mainly medium-thick sand intercalated with thin mud (composite type ① (MT1 type)), the channel + beach architecture unit combination and the channel + estuary bar architecture unit combination are well developed, and type II weak heterogeneous lithofacies are developed in single sand bodies.

[0027] The sand bodies with type III architecture are mainly isolated, and the sand-mud combination is mainly thick mud intercalated with thin fine sand (composite type ② (MT2 type)). The combination of channel + channel architecture units and channel + breach fan + natural levee + abandoned channel architecture units are well developed. Type III strong heterogeneous lithofacies are developed in single sand bodies.

[0028] The vertical combination types based on different configurations on a single well include: Class I + Class I, Class I + Class II, Class II + Class II, Class II + Class III, etc.

[0029] Step 3: Determine the sand-mud combination types of different sand body configurations of the channel sand body.

[0030] Combined with geological logging, a classification study of sand-mud combinations of each sand group was carried out, and it was clarified that the target sand group in the study area mainly developed three types of sand-mud combinations, including thick sand and thin silty mud (uniform type), medium-thick sand and thin mud (composite type ①), and thick mud and thin fine sand (composite type ②).

[0031] Thick sand intercalated with thin silty mud (uniform type (HT type)), with developed massive bedding and large-scale cross-bedding.

[0032] Medium-thick sand intercalated with thin mud (composite type ① (MT1 type)), with parallel bedding and large-scale cross-bedding.

[0033] Thick mud intercalated with thin fine sand (composite type ② (MT2 type)), with parallel bedding and small cross-bedding.

[0034] Among them, the sand body with thick sand and thin silty mud (uniform type) has the best physical properties, with an average porosity of about 12% and an average permeability of about 0.9.

[0035] Step 4: Determine the combination type of architectural units of the channel sand body.

[0036] Based on the similarity of logging curve morphology, physical properties and seismic attribute differences, the channel sand body stages were divided, the single sand body was identified, and the structural units were divided based on sedimentary microfacies. The single sand body mainly includes six types of structural units: developed side beach, channel filling deposits, estuary bar, breach fan, natural levee, and abandoned river channel; based on the vertical combination of structural units, the structural unit combination is divided into five categories, including developed side beach + side beach, side beach + channel filling deposits, channel filling deposits + estuary bar, channel filling deposits + breach fan + natural levee + abandoned river channel, channel filling deposits + channel filling deposits;

[0037] Among them, the sand bodies with developed side beaches + side beaches have the best physical properties, with an average porosity of 12%-14% and an average permeability of 0.8-0.9mD. The sand bodies with side beaches + channel filling deposits and channel filling deposits + estuary bars are second, with an average porosity of 10%-12% and an average permeability of 0.5-0.6mD.

[0038] Step 5: Determine the channel sand body facies.

[0039] Through detailed description of the core, single sand body lithofacies and rhythmic structure research was carried out, and combined with the electrical characteristics, an identification plate was established. It was clarified that the beach and river channel mainly developed blocky bedding and cross-bedding lithofacies combinations, uniform rhythm and positive rhythmic structure. The overall physical properties are good, with an average porosity of 12% and an average permeability of 0.934mD, which is conducive to the development of high-quality reservoirs.

[0040] Based on the differences in physical properties and logging response characteristics, lithofacies are classified into three categories: Class I homogeneous lithofacies, Class II weakly heterogeneous lithofacies, and Class III strongly heterogeneous lithofacies. Class I homogeneous lithofacies have thick sandstones, high porosity and permeability, high daily gas production, and stable sand distribution; Class I homogeneous lithofacies have low natural gamma GR (<69API), large acoustic time difference AC (70-79us / ft), and low density DEN (2.32-2.48g / cm 3 ).

[0041] Step 6: Combined with seismic attribute analysis

[0042] The strength of seismic amplitude reflection is combined to determine whether the river sand body is connected. Continuous strong reflection means that its connectivity is good, while weak reflection means that its connectivity is poor.

[0043] Step 7: Determine the sand body connectivity of the channel sand body based on the parameters of the channel sand body in steps 1-6.

[0044] According to the sand body superposition style, vertical configuration combination type, sand-mud combination type of different sand body configurations, configuration unit combination type, and lithofacies parameters, the sand body connectivity is divided into three levels: level I is excellent connectivity, level II is medium connectivity, and level III is poor connectivity.

[0045] Level I judgment criteria: the vertical configuration combination is Class I + Class II, or mainly Class I + Class II, the configuration unit combination type is a beach + beach configuration with single sand body development and good physical properties, the mud and sand combination is mainly homogeneous HT type (uniform type), the lithofacies is mainly homogeneous lithofacies, and the sand body contact relationship is scour and cutting type.

[0046] Level II judgment criteria: The vertical configuration combination is mainly Class II + Class II, the configuration unit combination type is the beach + channel, channel + estuary bar configuration with single sand body development and good physical properties, the sand and mud combination is mainly the weakly heterogeneous MT1 type (uniformity, composite type ①), the lithofacies is homogeneous lithofacies and weakly heterogeneous lithofacies, and the sand body contact relationship is the erosion contact type.

[0047] Level III judgment criteria: the vertical configuration combination is mainly Class II + Class III and Class III + Class III, the configuration unit combination type is channel + channel, channel + breach fan + natural levee + abandoned channel configuration with single sand body development and poor physical properties, the sand and mud combination is mainly of strong heterogeneous MT2 type (composite type ① and composite type ②), the lithofacies is weakly heterogeneous lithofacies and strongly heterogeneous lithofacies, and the sand body contact relationship is isolated.

[0048] Step 8: Verify with dynamic data from production wells

[0049] Combined with the dynamic data of the production wells, compare whether there is any influence between adjacent wells. If interference occurs, it means that the connectivity is good. Otherwise, it means that the connectivity is poor.

[0050] Beneficial Effects

[0051] The present invention evaluates the connectivity level of river sand bodies, combines seismic attribute differences and dynamic data analysis, and verifies the connectivity of river sand bodies through dynamic and static information fusion, so as to efficiently and accurately evaluate the strength of reservoir heterogeneity, providing a sufficient theoretical basis for the production and development of tight gas reservoirs in my country. It is of great significance to the "increase of reserves and production" of gas fields, and at the same time solves the problem of clean energy supply and demand in my country. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is the evaluation standard for the connectivity grade of river channel sand bodies;

[0053] Figure 2A This is the well-connected cross-section of the channel sand body of the No. 8 sand group in the study area;

[0054] Figure 2B This is an enlarged cross-section of the No. 8 sand group river channel sand body in the study area. Figure Ⅰ ;

[0055] Figure 2C It is the enlarged diagram of the well-connected cross-section of the channel sand body of the No. 8 sand group in the study area II;

[0056] Figure 2D This is an enlarged cross-section of the No. 8 sand group river channel sand body in the study area. Figure III ;

[0057] Figure 2E This is an enlarged cross-section of the No. 8 sand group river channel sand body in the study area. Figure IV ;

[0058] Figure 3 It is a schematic diagram of the vertical combination type of Class I + Class I;

[0059] Figure 4 It is a schematic diagram of the vertical combination type of Class II + Class II;

[0060] Figure 5 It is a schematic diagram of the vertical combination type of Class I + Class II;

[0061] Figure 6 It is a schematic diagram of the vertical combination type of Class II + Class III;

[0062] Figure 7 It is a typical profile I;

[0063] Figure 8 It is a typical profile II;

[0064] Fig. 9 It is a typical section III;

[0065] Fig.10 It is the river channel seismic attribute map and sand body distribution map where wells Q16-Q207 of sand group 8 in the study area are located;

[0066] Fig.11 This is the interference display diagram of Well Q16 and Well Q207 of Sand Formation No. 8 in the study area;

[0067] Fig.12 It is the river channel seismic attribute map and sand body distribution map of Q205-H1 and Q205-H2 wells in the No. 8 sand group in the study area;

[0068] Fig.13 It is a flow chart of the present invention. Specific embodiments

[0069] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0070] according to Fig.13 As shown in FIG. 1 , a method for verifying the connectivity of channel sand bodies in tight gas reservoirs based on dynamic and static information fusion includes the following steps:

[0071] Step 1: Determine the sand body superposition pattern of the channel sand body;

[0072] Step 2: Determine the vertical configuration combination type of the channel sand body;

[0073] Step 3: Determine the sand-mud combination types of different sand body configurations of the channel sand body;

[0074] Step 4: Determine the combination type of architectural units of the channel sand body;

[0075] Step 5: Determine the channel sand body facies;

[0076] Step 6: Combined with seismic attribute analysis;

[0077] Step 7: Determine the sand body connectivity of the channel sand body according to the parameters of the channel sand body in steps 1-6;

[0078] Step 8: Verify with dynamic data from production wells.

[0079] Example 1

[0080] according to Figure 1-9 As shown, the sand body superposition style of the channel sand body where the two wells Q16 and Q207 of the No. 8 sand group in the study area are located is the scour-cutting type, the vertical configuration combination type of the channel sand body is Class I + I, the sand-mud combination type is beach + beach, and the lithofacies is Class I homogeneous lithofacies. Therefore, based on the above information, it can be seen that the channel sand bodies where the two wells Q16 and Q207 of the No. 8 sand group in the study area are located have good connectivity.

[0081] according to Figure 10-11 As shown in the figure, for the river channel sand bodies where the two wells Q16 and Q207 of the No. 8 sand group in the study area are located, combined with seismic attributes, it can be seen that the river channel presents continuous strong reflection (vp<1.78, vs<1.78). Based on the dynamic data analysis of the two production wells, it can be seen that the well control radius of a single well is small, and the well control radius of most wells is smaller than the well spacing, and no interference is shown in production; the well control radius of Q16 well is 594m, and the bottom of the well is 499m away from the bottom of Q207 well. After the production of Q207 well was reduced (29↘200,000 cubic meters) on August 10, 2021, the oil pressure of Q16 well was restored, and the decline rate slowed down from 0.72MPa / Mon to 0.39MPa / Mon. The fusion of dynamic and static information such as geology, seismic, and dynamic data verifies that the sand body of this river channel has good connectivity.

[0082] Example 2

[0083] according to Fig.12 As shown in the figure, for the river channel sand bodies whose connectivity level has been evaluated, such as the river channel sand bodies where the two wells Q205-H1 and Q205-H2 of the No. 8 sand group in the study area are located, based on the previous geological analysis, it is believed that the river channel sand bodies have poor connectivity. Combined with the seismic attributes, it can be seen that the river channel presents discontinuous weak reflection (vp>1.78, vs>1.78). Based on the dynamic data analysis of the two production wells, it can be seen that this pressure recovery test shows that there is no interference between the Qiulin 205-H1 well and the Qiulin 205-H2 well. From July 25 to August 15, 2021, the Q205-H1 well was tested for pressure recovery, and from August 10 to August 18, 2021, the Q205-H2 well was tested for modified isochronous wells. During the opening of the Q205-H2 well, no interference was observed in the Q205-H1 well. The detection radius of the Q205-H1 well pressure recovery test was 77m, and the closest distance between the two wells in the horizontal section was 1.14km. The fusion of dynamic and static information such as geological, seismic, and dynamic data verified that the sand body connectivity of this river channel was poor.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. Verification method of channel sandbody connectivity in tight gas reservoirs based on dynamic and static information fusion, It is characterized in that The following steps are involved: Step 1: Determine the sand body superposition pattern of the channel sand body; Step 2: Determine the vertical configuration combination type of the channel sand body; Based on the sand body superposition style and sand-mud combination, architectural unit combination, lithofacies and rhythmic structure type and characteristics, three types of architecture are divided; The sand bodies with type I architecture are mainly scour cutting type and contact type. The sand-mud combination is mainly thick sand intercalated with thin silty mud, which is also called uniform type or HT type. The combination of side beach + side beach architecture units is developed. Type I homogeneous lithofacies is developed in single sand bodies, which is conducive to the development of high-quality reservoirs. The sand bodies with type II architecture are mainly contact type, and the sand-mud combination is mainly medium-thick sand intercalated with thin mud. Medium-thick sand intercalated with thin mud is also called composite type ① or MT1 type. The combination of channel + beach architecture unit and channel + estuary bar architecture unit is developed. Type II weak heterogeneous lithofacies is developed in single sand bodies. The sand bodies with type III architecture are mainly isolated, and the sand-mud combination is mainly thick mud intercalated with thin fine sand. Thick mud intercalated with thin fine sand is also called composite type ② or MT2 type. The combination of channel + channel architecture unit, channel + breach fan + natural levee + abandoned channel architecture unit combination is developed. Type III strong heterogeneous lithofacies is developed in single sand bodies. Based on the vertical combination types of different configurations on a single well, including: Class I + Class I, Class I + Class II, Class II + Class II, Class II + Class III Step 3: Determine the sand-mud combination types of different sand body configurations of the channel sand body; Combined with geological logging, the classification study of sand-mud combinations of each sand group was carried out, and it was clarified that the target sand group in the study area mainly developed three types of sand-mud combinations, including thick sand with thin silty mud, medium-thick sand with thin mud, and thick mud with thin fine sand; Thick sand intercalated with thin silty mud, with massive bedding and large-scale cross-bedding; Medium-thick sand intercalated with thin mud, with parallel bedding and large-scale cross-bedding; Thick mud intercalated with thin fine sand, with parallel bedding and small cross-bedding; The average porosity of the sand body with thick sand and thin silty mud is 12%, and the average permeability is 0.9; Step 4: Determine the combination type of architectural units of the channel sand body; Based on the similarity of logging curve morphology, physical properties and seismic attribute differences, the channel sand body stages were divided, the single sand body was identified, and the structural units were divided based on sedimentary microfacies; the single sand body mainly includes six types of structural units: developed side beach, channel filling deposits, estuary bar, breach fan, natural levee, and abandoned channel; based on the vertical combination of structural units, the structural unit combination was divided into five categories, including developed side beach + side beach, side beach + channel filling deposits, channel filling deposits + estuary bar, channel filling deposits + breach fan + natural levee + abandoned channel, channel filling deposits + channel filling deposits; The average porosity of the sand bodies with side beaches + side beaches is 12%-14%, and the average permeability is 0.8-0.9mD. The sand bodies with side beaches + river filling deposits and river filling deposits + estuary bars are second, with an average porosity of 10%-12% and an average permeability of 0.5-0.6mD. Step 5: Determine the channel sand body facies; Through the detailed description of the core, the single sand body lithofacies and rhythmic structure research was carried out, and the identification plate was established in combination with the electrical characteristics, which clarified that the beach and river channel mainly developed blocky bedding and cross-bedding lithofacies combination, uniform rhythm and positive rhythmic structure, among which the average porosity was 12% and the average permeability was 0.934mD, which was conducive to the development of high-quality reservoirs; Based on the differences in physical properties and logging response characteristics, lithofacies are classified into three categories: Class I homogeneous lithofacies, Class II weakly heterogeneous lithofacies, and Class III strongly heterogeneous lithofacies. Class I homogeneous lithofacies have thick sandstones, high porosity and permeability, high daily gas production, and stable sand distribution. Class I homogeneous lithofacies have natural gamma GR <69API, acoustic time difference AC of 70-79us / ft, and density DEN of 2.32-2.48g / cm 3 Step 6: Combined with seismic attribute analysis; The strength of seismic amplitude reflection is combined to determine whether the channel sand body is connected. Continuous strong reflection is considered to have good connectivity, while weak reflection is considered to have poor connectivity. Step 7: Determine the sand body connectivity of the channel sand body according to the parameters of the channel sand body in steps 1-6; According to the sand body superposition style, vertical configuration combination type, sand-mud combination type of different sand body configurations, configuration unit combination type, and lithofacies parameters, the sand body connectivity is divided into three levels: level I is excellent connectivity, level II is medium connectivity, and level III is poor connectivity. Level I judgment criteria: the vertical configuration combination is type I + type II, or mainly type I + type II, the configuration unit combination type is beach + beach configuration, the sediment combination is mainly homogeneous HT type, the lithofacies is mainly homogeneous lithofacies, and the sand body contact relationship is scour cutting type; Level II judgment criteria: The vertical configuration combination is mainly type II + type II, the configuration unit combination type is the single sand body developed side beach + river channel, river channel + estuary bar configuration, the sand and mud combination is mainly the weakly heterogeneous MT1 type, the lithofacies is homogeneous lithofacies and weakly heterogeneous lithofacies, and the sand body contact relationship is the scour contact type; Class III judgment criteria: The vertical configuration combination is mainly Class II + Class III and Class III + Class III, the configuration unit combination type is channel + channel, channel + breach fan + natural levee + abandoned channel configuration with single sand body development, the sand-mud combination is mainly MT2 type with strong heterogeneity, the lithofacies is weak heterogeneous lithofacies and strong heterogeneous lithofacies, and the sand body contact relationship is isolated type; Step 8: Verify with dynamic data of production wells; Combined with the dynamic data of production wells, compare whether there is any impact between adjacent wells; If interference occurs, it means the connectivity is good, otherwise it means the connectivity is poor.

2. The method for verifying the connectivity of river channel sand bodies in tight gas reservoirs based on dynamic and static information fusion according to claim 1, It is characterized in that Step 1 also includes: Combined with geological logging, the classification of sand body superposition styles of each sand group was carried out, and three types of sand body superposition styles were divided, including scour cutting type, scour contact type, and isolated type; The scour-cut sand body superposition style is formed under stable and strong hydrodynamic conditions. The early river channel is scour-cut by the late river channel, which is often manifested as the superposition of multi-stage river channel sand bodies and the development of high-quality reservoirs. The scour contact sand body superposition style is easily formed under the condition of frequent changes in hydrodynamic conditions, and the mudstone thickness is large; The isolated sand body superposition style is easily formed under the conditions of frequent migration and diversion of the river channel, and the mudstone thickness is large.

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