CN113534248A

CN113534248A - Method, device and system for quantitatively analyzing closure of trap fault

Info

Publication number: CN113534248A
Application number: CN202010303957.9A
Authority: CN
Inventors: 景紫岩; 卫平生; 方乐华; 石兰亭; 景紫威; 陈广坡; 张亚军; 苏玉平; 李双文; 赵伟
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2020-04-17
Filing date: 2020-04-17
Publication date: 2021-10-22

Abstract

The invention provides a closure quantitative analysis method, a device and a system for a trapped fault, wherein the method comprises the following steps: obtaining a three-dimensional data body of a mudstone smearing type fault to be drilled and trapped, wherein the three-dimensional data body is obtained by scanning and reconstructing a fault simulation model of the mudstone smearing type fault to be drilled and trapped; obtaining fracture zone mudstone smearing thickness and fracture mud ratio of a plurality of sampling points according to the three-dimensional data volume; fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio; determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped; and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point. The method can quantitatively analyze the closure of the closed fault of the to-be-drilled ring, and has high accuracy.

Description

Method, device and system for quantitatively analyzing closure of trap fault

Technical Field

The application relates to the technical field of oil and gas exploration, in particular to a closure quantitative analysis method, device and system for a trap fault.

Background

The so-called trap fault is a fault of the formation. After the stratum is fractured, the fault is formed by dislocation. Only fracture, no dislocation, that is, crack. The extension range of the crack is small, and the extension range of the trap fault is large. The fracture usually functions as a seepage channel, and the function of the trapping fault is complex, so that oil and gas are sometimes sealed and sometimes conducted. Faults have a dislocation which is the result of shearing which can break the rock on both sides, some of which falls off to fill the cracks and then evolve into a layer of rock which is either wide or narrow. Thus, a trapped fault is a layer of clastic rock that is formed after packing. Clastic rock has porosity and also permeability. Due to the fact that the properties of rocks on two sides of the trapped fault are different, the physical properties of fault clastic rocks are greatly different and belong to heterogeneous strata, and some parts are low-porosity and low-permeability and some parts are high-porosity and high-permeability. When the fault rock opposite to the reservoir layer is clastic rock with relatively poor physical property, the fault plays a role in sealing oil and gas. When the fault rock opposite to the reservoir layer is clastic rock with relatively good physical property, the fault plays a role in transporting and guiding oil and gas. However, the fault can not seal water but only oil gas, and the mechanism of sealing oil gas by the fault is completely the same as that of the cover layer. The fault is the transportation oil gas or the sealing oil gas, which is not related to the generation of the fault, the normal and inverse properties and the tension and pressure properties. Underground faults are closed and cannot be opened, and the closed faults can seal oil gas and can also conduct the oil gas.

The formation movement may again damage the fault but only change the properties of the fault rock, for example a crack may be created in the fault rock but it is not possible to change the closure properties of the fault. Trap fault sealing is one of the core problems in petroleum geology research, and is well concerned by petroleum geologists at home and abroad, 80% of fault oil and gas reservoirs are controlled by fault sealing, and trap fault layer rock mudstone smearing type is the main sealing type. The trap fault closure analysis is directly related to whether the trap under fault control can be accurately judged to be stored or not and the oil gas height. In the exploration and production practice of the petroleum industry, whether the oil-gas height and the trap area of the fault block trap can be accurately judged and predicted is important for improving the oil-gas exploration benefit, and exploration decision deployment and investment are directly influenced.

In order to determine the fault closure, a plurality of methods for quantitatively analyzing the closure of the trapped fault exist, for example, the closure of a target fault is determined by an SGR (fault mud ratio) method according to well drilling data. However, in specific implementation, the existing evaluation parameter model is too ideal, only a simple proportional relation between the shale content and the fracture distance is considered, and particularly, the accuracy is not high when no well or few well zones are analyzed.

Disclosure of Invention

The embodiment of the invention provides a closure quantitative analysis method of a confined fault, which is used for quantitatively analyzing the closure of the confined fault to be drilled and has high accuracy and comprises the following steps:

obtaining a three-dimensional data body of a mudstone smearing type fault to be drilled and trapped, wherein the three-dimensional data body is obtained by scanning and reconstructing a fault simulation model of the mudstone smearing type fault to be drilled and trapped;

obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data volume;

fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio;

determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped;

and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point.

The embodiment of the invention provides a closure quantitative analysis device of a confined fault, which is used for quantitatively analyzing the closure of the confined fault to be drilled and has high accuracy, and comprises:

the device comprises a first module, a second module and a third module, wherein the first module is used for obtaining a three-dimensional data body of a mudstone smearing type fault to be drilled and trapped, and the three-dimensional data body is obtained by scanning and reconstructing a fault simulation model of the mudstone smearing type fault to be drilled and trapped;

the second module is used for obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data body;

the third module is used for fitting the fracture zone mudstone smearing thickness and the fracture zone mudstone ratio of the plurality of sampling points and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fracture zone mudstone ratio;

the fourth module is used for determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mudstone ratio of the sampling points of the mudstone smearing type fault to be drilled and closed;

and the fifth module is used for analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point.

The embodiment of the invention provides a closure quantitative analysis system of a confined fault, which is used for quantitatively analyzing the closure of the confined fault to be drilled and has high accuracy, and the system comprises: a fault simulation model construction unit, a scanning unit and a closure quantitative analysis device for the trap fault,

the fault simulation model construction unit is used for constructing a fault simulation model of a mudstone smearing type fault to be drilled and trapped;

the scanning unit is used for scanning the fault simulation model, generating surface data of a mudstone smearing type fault to be drilled and trapped, and sending the surface data to the closure quantitative analysis device for the trapped fault;

the closure quantitative analysis device of the trap fault is used for reconstructing the received surface data to obtain a three-dimensional data volume; obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data volume; fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio; determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped; and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point.

The embodiment of the invention also provides computer equipment which comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the processor realizes the closure quantitative analysis method of the trap fault when executing the computer program.

An embodiment of the present invention further provides a computer-readable storage medium, which stores a computer program for executing the method for quantitatively analyzing the closure of the trap fault.

In the embodiment of the invention, a three-dimensional data body of a mudstone smearing type fault to be drilled and trapped is obtained, wherein the three-dimensional data body is obtained by scanning and reconstructing a fault simulation model of the mudstone smearing type fault to be drilled and trapped; obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data volume; fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio; determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped; and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point. In the process, the method can analyze the sealing performance of the closed fault of the mudstone to be drilled, and in the analysis process, the fitting coefficient of the mudstone smearing thickness of the fractured zone and the ratio of the fault mud is determined, and the fitting coefficient can represent the effective smearing degree of the mudstone, so that the mudstone smearing sealing factor of the fractured zone is determined more accurately, and the accuracy of finally analyzing the sealing performance of each sampling point of the mudstone smearing type fault of the closed fault to be drilled is higher.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts. In the drawings:

FIG. 1 is a flow chart of a method for closure quantification of a trapped fault in an embodiment of the present invention;

FIG. 2 is a detailed flowchart of a method for quantitatively analyzing the closure of a trap fault according to an embodiment of the present invention;

FIG. 3 is a front view of a physical simulation model of a to-be-drilled coil constructed in an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of a fracture zone scanned in accordance with an embodiment of the present invention;

FIG. 5 is a schematic diagram of a three-dimensional data volume according to an embodiment of the invention;

FIG. 6 is a diagram of a relationship chart in an embodiment of the invention;

FIG. 7 is a schematic view of a closed quantitative analysis apparatus for a trap fault according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a closed quantitative analysis system for a trapped fault in an embodiment of the present invention;

FIG. 9 is a diagram of a computer device in an embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings. The exemplary embodiments and descriptions of the present invention are provided to explain the present invention, but not to limit the present invention.

In the description of the present specification, the terms "comprising," "including," "having," "containing," and the like are used in an open-ended fashion, i.e., to mean including, but not limited to. Reference to the description of the terms "one embodiment," "a particular embodiment," "some embodiments," "for example," etc., means that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. The sequence of steps involved in the embodiments is for illustrative purposes to illustrate the implementation of the present application, and the sequence of steps is not limited and can be adjusted as needed.

Fig. 1 is a flowchart of a method for quantitatively analyzing the closure of a trapped fault according to an embodiment of the present invention, as shown in fig. 1, the method includes:

101, obtaining a three-dimensional data body of a mudstone smearing type fault to be drilled and trapped, wherein the three-dimensional data body is obtained by scanning and reconstructing a fault simulation model of the mudstone smearing type fault to be drilled and trapped;

102, obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data body;

step 103, fitting the fracture zone mudstone coating thickness and the fracture zone mudstone ratio of the plurality of sampling points, and determining a fitting coefficient of the fracture zone mudstone coating thickness and the fracture zone mudstone ratio;

104, determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and closed;

and 105, analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fracture zone of each sampling point.

In the embodiment of the invention, the closure of the to-be-drilled confined fault can be analyzed, and in the analysis process, the fitting coefficient of the mudstone smearing thickness of the fractured zone and the fault mud ratio is determined, and the fitting coefficient can represent the effective smearing degree of the mudstone, so that the mudstone smearing closure factor of the fractured zone is more accurately determined, and the accuracy of finally analyzing the closure of each sampling point of the mudstone smearing type fault of the to-be-drilled confined fault is higher.

In a conventional fault closure analysis method, quantitative evaluation is generally performed by using a fault rock mud ratio SGR, and a certain effect is obtained. The existing method mostly only uses logging data as input data to calculate, and the method has two defects that firstly, the method only relates to the shale content and the fault distance of a certain well and does not consider the influence of the change of lithology, and secondly, the mudstone smearing continuity and heterogeneity are not considered, the sealing threshold value cannot be determined in the area where the logging data is incomplete or the logging data is not available, so that the existing sealing analysis method also has the technical problem of low scientificity and accuracy. The inventors have analyzed the root cause of the above technical problems and considered that mudstone smear of the fault should be considered, including continuity and validity, i.e., the closure of mudstone smear type faults should be sufficiently analyzed.

In one embodiment, obtaining a three-dimensional data volume of a mudstone smear-type fault to be drilled for entrapment includes:

determining the construction parameters and fault deformation stress of the physical simulation model of the to-be-drilled encloser according to the geological background information, fault data and layer data of the to-be-drilled encloser;

the method comprises the steps of obtaining surface data of a mudstone smearing type fault to be drilled and trapped, conducting three-dimensional reconstruction on the surface data, and obtaining a three-dimensional data body of the mudstone smearing type fault to be drilled and trapped, wherein the surface data are obtained by scanning a fault simulation model, the fault simulation model is obtained by loading fault deformation stress on a physical simulation model to be drilled and trapped, and the physical simulation model to be drilled and trapped is constructed based on construction parameters.

In specific implementation, before determining the construction parameters of the physical simulation model of the to-be-drilled well, the method further comprises the following steps of:

and acquiring fault data and layer data of the trap to be drilled according to the post-stack seismic data of the trap to be drilled.

In the above embodiment, the fault data and the horizon data of the to-be-drilled trap may be obtained through interpretation in a seismic interpretation system or other related software (for example, Geoeast software, Landmark software, or Geoframe software) according to the post-stack seismic data, and the section spreading rule and the fault distance information may also be obtained. According to the result of the explanation, the sand shale stratum can be obtained, the fault data and the horizon data of the trap to be drilled which are obtained by the explanation provide accurate parameters and basis for physical simulation, and the accuracy and the scientificity of a physical simulation model of the trap to be drilled in the later period are ensured.

And then, determining the construction parameters and the fault deformation stress of the physical simulation model of the to-be-drilled encirclement according to the geological background information, the fault data and the horizon data of the to-be-drilled encirclement, wherein the process is also called scheme design for constructing the physical simulation model of the to-be-drilled encirclement.

In one embodiment, the construction parameters of the physical simulation model to be drilled include one or any combination of model boundary, physical simulation model similarity ratio, physical simulation duration similarity ratio, simulated formation material and simulated mudstone material.

Based on the embodiment, the steps of constructing the physical simulation model of the to-be-drilled coil closure are as follows:

s1: determining a model boundary, a physical simulation model similarity ratio and a physical simulation duration similarity ratio of a to-be-drilled enclosed physical simulation model according to geological background information, fault data and layer data of the to-be-drilled enclosed physical simulation model, wherein the model boundary, the physical simulation model similarity ratio and the physical simulation duration similarity ratio specifically comprise the size and the thickness of the to-be-drilled enclosed physical simulation model, the number of layers and the thickness of a mudstone layer and a simulation displacement deformation (a section fracture distance is the maximum displacement);

s2: determining a simulated formation material and a simulated mudstone material according to a material similarity principle; for example, quartz sand is used for simulating a sandstone layer, clay is used for simulating a mudstone layer, and the two materials are similar to each other, have higher stability and are generally adopted at present.

S3: and constructing the physical simulation model of the to-be-drilled ring closure according to the construction parameters of the physical simulation model of the to-be-drilled ring closure.

And after the physical simulation model of the to-be-drilled ring closure is constructed, loading fault deformation stress on the physical simulation model of the to-be-drilled ring closure to obtain a fault simulation model. During specific implementation, the stratum can be promoted to move in a staggered manner through the loaded fault deformation stress in the deformation sand box to form a fault, the mudstone layer descends through the upper plate to generate a dragging and smearing phenomenon, a mudstone smearing layer is formed, and finally a mudstone smearing type fault is formed.

In one embodiment, the mudstone is smeared with the thickness of the mudstone at a position losing continuity, namely a fault plugging failure position, and the minimum mudstone thickness H of fault plugging can be determined by analyzing a mudstone smearing broken position, also called a fracture zone mudstone smearing thickness H.

In one embodiment, when the fault dislocation reaches the preset maximum displacement, the fault deformation stress can be stopped, the structural deformation is completed, and the fault simulation model is obtained.

In step 101, a three-dimensional data volume of a mudstone smearing type fault to be drilled and trapped is obtained, the three-dimensional data volume is obtained by scanning and reconstructing a fault simulation model of the mudstone smearing type fault to be drilled and trapped, in the specific implementation, scanning methods such as industrial CT can be adopted when the fault simulation model is scanned, and when the industrial CT is adopted for description, dynamic monitoring scanning positions, scanning frequencies, scanning intervals and the like can be set according to the precision requirement, so that the scanning precision is ensured. In addition, when the fault simulation model is scanned, a fracture zone in the fault simulation model is mainly scanned, and surface data of a mudstone smearing type fault to be drilled and trapped are obtained. The more surface data that is obtained, the higher the final fracture band accuracy. The specific scanning process may be as follows:

s1: and setting different acquisition intervals according to the research precision requirement. And (4) placing the position of the fault simulation model needing to be scanned under the industrial CT to scan the surface data.

S2: and pushing the fault simulation model into an industrial CT at a constant speed, scanning different surfaces, and obtaining continuous surface data at equal intervals.

In one embodiment, a difference method or a fitting method is adopted to carry out three-dimensional reconstruction on the surface data, and a three-dimensional data body of the mudstone smearing type fault to be drilled and trapped is obtained.

In the above embodiment, the three-dimensional data volume obtained by the three-dimensional reconstruction method has high accuracy. The three-dimensional data volume is convenient for the omnibearing recognition of the fault simulation model. Three-dimensional reconstruction is carried out on the surface data, namely, unknown surface data (surface data between two groups of adjacent surface data) is constructed through known surface data obtained by scanning, and finally, all the surface data are recombined to form a three-dimensional data body. The reconstruction method such as difference can be implemented by software or other computer equipment. The surface data is three-dimensionally reconstructed by using a difference method, that is, the surface data between two sets of adjacent surface data (for example, two gray-scale scanning images) is obtained by performing difference between the two sets of adjacent surface data by using a mathematical method such as a gaussian difference. And (3) performing three-dimensional reconstruction on the face data by adopting a fitting method, namely fitting the forms of other face data according to the change rule of the face data through certain known face data to obtain the unknown face data.

According to the three-dimensional data body, the fracture zone mudstone smearing thickness and the fault mud ratio of a plurality of sampling points can be obtained in various ways, and one embodiment is given below.

In one embodiment, obtaining fracture zone mudstone smear thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data body comprises:

extracting fracture zone attribute information of mudstone smearing type faults from the three-dimensional data body, wherein the attribute information comprises fracture zone mudstone smearing thicknesses of a plurality of sampling points, fault distances of the faults and shale content of the fracture surfaces;

and calculating the fault mud ratio of the plurality of sampling points according to the fault distance of the faults of the plurality of sampling points and the mud content of the fracture surface.

In the above embodiment, the fracture zone attribute information includes fracture zone mudstone smear thickness, fault distance and fracture surface mudiness content of a plurality of sampling points, and the fault distance and fracture surface mudiness content of a plurality of sampling points calculate the fault mud ratio of a plurality of sampling points, and the calculation formula is as follows:

SGR＝Z/D (1)

the method comprises the following steps of sampling points, wherein SGR is the fault mud ratio of each sampling point, Z is the mud content of the section of each sampling point, the unit is cm, D is the fault distance of the section of each sampling point, and the unit is cm.

There are various methods for extracting fracture zone attribute information of mudstone smear-type faults in the above embodiments, and one of the embodiments is given below.

In one embodiment, extracting fracture zone attribute information of mudstone smear-type faults from the three-dimensional data volume includes:

identifying a broken belt body from the three-dimensional data body according to the gray characteristic value of the broken belt body;

and extracting the attribute information of the broken belt body.

In the above embodiment, the gray characteristic value of the broken belt body is generally obtained according to the analysis of the simulated material, the gray characteristic value of the broken belt body is generally about 430, and the broken belt body of the mudstone smearing type fault can be identified according to the mudstone gray value. The identification of the broken tape can be realized by means of gray scale processing software such as VG, etc., although other manners can be adopted, and all the related modifications are within the scope of the present invention. In the sand-mudstone model, the gray characteristic value of sandstone and mudstone is 436, namely, mudstone is greater than 436, and sandstone is less than 436.

In the foregoing embodiment, fitting the fracture zone mudstone smear thickness and the fracture mud ratio of a plurality of sampling points can be realized by the fracture zone mudstone smear thickness and the SGR chart. It is known from the foregoing that the minimum fault closure mudstone thickness H, also called fracture zone mudstone coating thickness H, can be determined by analyzing the mudstone coating break, and the fracture zone mudstone coating thickness H and SGR are plotted on a chart, so as to obtain a chart of the relationship between the fracture zone mudstone coating thickness and the SGR, and based on the relationship chart, a fitting coefficient of the fracture zone mudstone coating thickness and the fault mud ratio is determined.

In one embodiment, when the fitting of the fracture zone mudstone smear thickness and the fault mud ratio of the plurality of sampling points is performed, the fracture zone mudstone smear thickness and the fault mud ratio of the plurality of sampling points are in a linear relation.

In the above embodiment, the fitting formula of the linear relationship may be as follows:

H＝A·SGR+B (2)

wherein H is the coating thickness of the mudstone in the fracture zone;

a is the fitting coefficient.

B is a constant parameter.

In the fitting formula, the coating thickness of the mudstone in the fracture zone and the ratio of the mudstone are in a linear relation, namely the larger the coating thickness of the mudstone in the fracture zone is, the larger the ratio of the mudstone in the fracture zone is, and the better the sealing performance is. According to statistics, when the smearing thickness of the mudstone in the longitudinal axis fracture zone is 0.1cm, the corresponding SGR is 18 percent, namely, the mudstone with the thickness of less than 0.1cm loses continuity and is ineffectively smeared, and the corresponding SGR with the thickness of less than 18 percent cannot play an effective plugging role. Therefore, by using the method, the extreme point of continuous smearing of the mudstone, namely the SGR lower limit value of fault sealing can be accurately defined on the relation chart.

In one embodiment, the fracture zone mudstone smearing closing factor of a plurality of sampling points is determined according to the fitting coefficient and the fault mud ratio of the sampling points of the mudstone smearing type fault to be drilled and closed by adopting the following formula:

SGRN＝A·SGR+C (3)

wherein, SGRN coats a sealing factor for the fractured zone mudstone of each sampling point;

a is a fitting coefficient;

c is a constant parameter;

SGR is the fault mud ratio for each sample point.

In the above embodiment, the physical meaning of the fitting coefficient is to represent the effective mudstone smearing degree, which is also called as effective continuous mudstone smearing contribution rate, is related to the regional geological features, the value range of the fitting coefficient is 0-1, more specifically, the value of the fitting coefficient a is 0.62-0.67, the mudstone smearing sealing factor of the fractured zone obtained by the calculation of the formula considers the effective mudstone smearing degree, considers the effectiveness and the heterogeneity of the mudstone smearing, but not roughly and simply calculates all the formation mudstones, compared with the fault mudstone ratio analysis of the mudstone not represented by the effective mudstone smearing degree, the method can more accurately analyze the sealing performance of the mudstone smearing type fault to be drilled and trapped, because the effective mudstone smearing degree represented by the fitting coefficient is from quantitative physical simulation and analysis, the method is suitable for the real situation under the set geological conditions, the reliability is high, and the scientificity is strong, more approaches true underground core characteristics. In fact, the fitting coefficients may have different values according to different geological conditions of different blocks.

In one embodiment, the method for analyzing the sealing performance of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing sealing factor of the fracture zone of each sampling point comprises the following steps:

determining a threshold value of a sealing factor applied to fractured zone mudstone to be drilled and trapped;

for each sampling point, if the fracture zone mudstone smearing closing factor of the sampling point is larger than the threshold value, closing of the sampling point is determined; otherwise, the sampling point is not closed.

In an embodiment, the method further comprises: and determining whether to drill the drilling collar according to the sealing performance of the mudstone smearing type fault.

Particularly, according to the process of calculating the fitting coefficient by the method, industrial CT scanning can be performed through field geological outcrop sampling and then the similar steps are obtained. And shall also fall within the scope of the present application.

Based on the above embodiment, the present invention provides the following embodiment to describe a detailed flow of a method for quantitatively analyzing a closure of a trap fault, fig. 2 is a detailed flow chart of the method for quantitatively analyzing a closure of a trap fault according to the embodiment of the present invention, as shown in fig. 2, in an embodiment, the detailed flow of the method for quantitatively analyzing a closure of a trap fault includes:

step 201, acquiring fault data and layer data of the trap to be drilled according to the post-stack seismic data of the trap to be drilled;

step 202, determining construction parameters and fault deformation stress of a physical simulation model of the to-be-drilled encloser according to geological background information, fault data and horizon data of the to-be-drilled encloser;

step 203, acquiring surface data of a mudstone smearing type fault to be drilled and trapped, and performing three-dimensional reconstruction on the surface data to acquire a three-dimensional data body of the mudstone smearing type fault to be drilled and trapped, wherein the surface data is acquired by scanning a fault simulation model, and the fault simulation model is acquired by loading fault deformation stress on a physical simulation model to be drilled and trapped;

step 204, identifying a broken belt body from the three-dimensional data body according to the gray characteristic value of the broken belt body;

step 205, extracting attribute information of a fracture belt body, wherein the attribute information comprises fracture belt mudstone smearing thickness, fault distance and fracture surface mudiness content of a plurality of sampling points;

step 206, calculating fault mud ratios of a plurality of sampling points according to fault distances and the mud content of the fracture surfaces of the plurality of sampling points;

step 207, fitting the fracture zone mudstone coating thickness and the fracture zone mudstone ratio of the plurality of sampling points, and determining a fitting coefficient of the fracture zone mudstone coating thickness and the fracture zone mudstone ratio;

208, determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and closed;

step 209, determining a threshold value of a sealing factor applied to the fractured zone mudstone to be cased;

step 210, for each sampling point, if the fracture zone mudstone smearing closing factor of the sampling point is larger than the threshold value, closing of the sampling point is determined; otherwise, the sampling point is not closed.

Of course, it is understood that other variations of the detailed flow of the method for quantitatively analyzing the closure of the trap fault may be adopted, and the related variations should fall within the scope of the present invention.

A specific example is given below to illustrate the specific application of the method for closure quantitative analysis of a trapping layer.

And S11, loading the post-stack seismic data of the trap to be drilled into a seismic interpretation system or other related software such as Geoaast software, and interpreting to obtain fault data and horizon data of the trap to be drilled.

S12, determining a model boundary, a physical simulation model similarity ratio and a physical simulation duration similarity ratio of the to-be-drilled encirclement physical simulation model according to geological background information, fault data and layer data of the to-be-drilled encirclement, wherein the model boundary, the physical simulation model similarity ratio and the physical simulation duration similarity ratio specifically comprise the size and the thickness of the to-be-drilled encirclement physical simulation model, the number of layers and the thickness of a mudstone layer and a simulation displacement deformation amount, and in the embodiment, the size of the to-be-drilled encirclement physical simulation model is 48cm multiplied by 24cm by 26 cm; the mud rock layer is 3 layers, and the thickness of the layer is 1.5 cm; determining the simulation displacement deformation of the physical simulation model of the to-be-drilled ring closure according to the fault-section value of the fault interpreted by the post-stack seismic data body, namely the fault-section is the maximum displacement, and is 9cm in the example; in this embodiment, the quartz sand simulates a sandstone layer, and the clay simulates a shale layer. Fig. 3 is a front view of a physical simulation model of a to-be-drilled well casing constructed in an embodiment of the present invention.

S13: and loading the fault deformation stress on the to-be-drilled-ring closed physical simulation model to obtain a fault simulation model, and forming a mudstone smearing zone.

S14: and processing the fault simulation model, acquiring a model containing the core position of the fracture zone in order to achieve better scanning and processing effects, processing the fault simulation model, and cutting off corners to obtain a 14cm × 15cm × 17cm scanning model. Industrial CT scanning is performed at scanning intervals of 0.5cm, fig. 4 is a schematic cross-sectional view of a fracture zone obtained by scanning in the embodiment of the present invention, and surface data is formed, where 30 fracture zone cross-sections are obtained by scanning, stored in a DICOM format, and subjected to visualization processing and three-dimensional reconstruction through a powerful graphics workstation. A 3D model is established by using a professional three-dimensional reconstruction software Mimics through an interpolation method and is edited to obtain a three-dimensional data volume, and fig. 5 is a schematic diagram of the three-dimensional data volume in the embodiment of the present invention.

S15: according to the gray characteristic value of the fracture zone body, the fracture zone body is identified from the three-dimensional data body, sand mudstones are distinguished in the Mimics software according to the gray characteristic value, and through analysis, the gray characteristic value of the sand mudstone is 436, the sand mudstone is greater than 436, and the sand mudstone is less than 436. And extracting attribute information of the fracture belt body, wherein the attribute information comprises fracture belt mudstone smearing thickness of a plurality of sampling points, fault distance of a fault and the mud content of a fracture surface.

Calculating fault mud ratios SGR of the multiple sampling points according to fault distances of faults of the multiple sampling points and the mud content of the cross sections; generating a scatter diagram by the obtained mudstone smearing thickness value H and SGR, forming a relation chart of the mudstone smearing thickness value H and the SGR, and determining a fitting coefficient of the mudstone smearing thickness of the fractured zone and the fault mud ratio by fitting based on the relation chart, wherein the fitting formula can be as follows:

H＝0.6248·SGR+0.032

wherein 0.6248 is a fitting coefficient and is also a slope of a curve in the relation plate, fig. 6 is a schematic diagram of the relation plate in the embodiment of the present invention, and the fitting coefficient 0.6248 represents an effective mudstone smearing degree, which is also referred to as an effective continuous mudstone smearing contribution rate.

S16: according to the formula (3), the fracture zone mudstone smearing closure factor of each sampling point can be obtained, and the parameter C in the formula (3) is 0 in the embodiment.

S17: determining a threshold value of a sealing factor for smearing the mudstone in the fractured zone to be drilled and trapped, wherein the SGR lower limit value of the known fault sealing is 18%, in the embodiment, the threshold value of the sealing factor for smearing the mudstone in the fractured zone to be drilled and trapped is determined to be 18%, and for each sampling point, if the sealing factor for smearing the mudstone in the fractured zone of the sampling point is greater than the threshold value, determining the sealing of the sampling point; otherwise, the sampling point is not closed. Therefore, the weak point of the sealing performance is found out, and the drilling risk is avoided.

In summary, in the method provided by the embodiment of the present invention, a three-dimensional data volume of a mudstone smear-type fault to be drilled and trapped is obtained, where the three-dimensional data volume is obtained by performing scanning reconstruction on a fault simulation model of the mudstone smear-type fault to be drilled and trapped; obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data volume; fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio; determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped; and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point. In the process, the method can analyze the sealing performance of the closed fault of the mudstone to be drilled, and in the analysis process, the fitting coefficient of the mudstone smearing thickness of the fractured zone and the ratio of the fault mud is determined, and the fitting coefficient can represent the effective smearing degree of the mudstone, so that the mudstone smearing sealing factor of the fractured zone is determined more accurately, and the accuracy of finally analyzing the sealing performance of each sampling point of the mudstone smearing type fault of the closed fault to be drilled is higher. In addition, the precision of the attribute information of the mudstone smearing type fault is improved by using the post-stack seismic data, the precision of the obtained three-dimensional data volume is high by using advanced means of physical simulation and industrial CT data quantitative acquisition and analysis, the problems of idealization of a calculation model, incomplete considered factors and low scientificity and accuracy in the existing fault closure analysis are solved quantitatively, scientific basis is provided for closure evaluation, leakage points are screened out by accurately evaluating the closure, the drilling is carried out to avoid investment risks, the method has good technical application prospect and economic benefit, the drilling success rate is improved, and the technical effect of evaluating the fault block trap according to the closure of the fault with higher precision is achieved.

Based on the same inventive concept, the embodiment of the invention also provides a closure quantitative analysis device for the trapped fault, which is described in the following embodiment. Because the principle of these solutions is similar to the closure quantitative analysis method of the trap fault, the implementation of the device can be referred to the implementation of the method, and the repeated parts are not repeated.

Fig. 7 is a schematic diagram of a closure quantitative analysis apparatus for a trap fault according to an embodiment of the present invention, as shown in fig. 7, the apparatus includes:

the device comprises a first module 701, a second module and a third module, wherein the first module 701 is used for obtaining a three-dimensional data body of a mudstone smearing type fault to be drilled and trapped, and the three-dimensional data body is obtained by scanning and reconstructing a fault simulation model of the mudstone smearing type fault to be drilled and trapped;

a second module 702, configured to obtain fracture zone mudstone smearing thickness and fault mud ratio of multiple sampling points according to the three-dimensional data volume;

a third module 703, configured to fit the fracture zone mudstone smearing thickness and the fracture zone mudstone ratio of the multiple sampling points, and determine a fitting coefficient of the fracture zone mudstone smearing thickness and the fracture zone mudstone ratio;

a fourth module 704, configured to determine fracture zone mudstone smearing closure factors of multiple sampling points according to the fitting coefficient and fault mudstone ratios of the multiple sampling points of the mudstone smearing type fault to be drilled and trapped;

a fifth module 705, configured to analyze the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point.

In an embodiment, the third module 703 is specifically configured to:

when the fractured zone mudstone smearing thickness and the fractured zone mudstone ratio of the plurality of sampling points are fitted, the fractured zone mudstone smearing thickness and the fractured zone mudstone ratio of the plurality of sampling points are in a linear relation.

In an embodiment, the second module 702 is specifically configured to:

and extracting the attribute information of the broken belt body.

In an embodiment, the first module 701 is specifically configured to:

and performing three-dimensional reconstruction on the surface data by adopting a difference method or a fitting method to obtain a three-dimensional data body of the mudstone smearing type fault to be drilled and trapped.

In an embodiment, the fifth module 705 is specifically configured to:

In summary, in the apparatus provided in the embodiment of the present invention, a three-dimensional data volume of a mudstone smear-type fault to be drilled and trapped is obtained, where the three-dimensional data volume is obtained by performing scanning reconstruction on a fault simulation model of the mudstone smear-type fault to be drilled and trapped; obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data volume; fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio; determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped; and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point. In the process, the method can analyze the sealing performance of the closed fault of the mudstone to be drilled, and in the analysis process, the fitting coefficient of the mudstone smearing thickness of the fractured zone and the ratio of the fault mud is determined, and the fitting coefficient can represent the effective smearing degree of the mudstone, so that the mudstone smearing sealing factor of the fractured zone is determined more accurately, and the accuracy of finally analyzing the sealing performance of each sampling point of the mudstone smearing type fault of the closed fault to be drilled is higher. In addition, the precision of the attribute information of the mudstone smearing type fault is improved by using the post-stack seismic data, the precision of the obtained three-dimensional data volume is high by using advanced means of physical simulation and industrial CT data quantitative acquisition and analysis, the problems of idealization of a calculation model, incomplete considered factors and low scientificity and accuracy in the existing fault closure analysis are solved quantitatively, scientific basis is provided for closure evaluation, leakage points are screened out by accurately evaluating the closure, the drilling is carried out to avoid investment risks, the method has good technical application prospect and economic benefit, the drilling success rate is improved, and the technical effect of evaluating the fault block trap according to the closure of the fault with higher precision is achieved.

The embodiment of the present invention further provides a system for quantitatively analyzing the closure of a trapping fault, and fig. 8 is a schematic diagram of the system for quantitatively analyzing the closure of a trapping fault in the embodiment of the present invention, including: a fault simulation model construction unit 801, a scanning unit 802, and the device 803 for quantitatively analyzing the sealing of the trapped fault,

a fault simulation model construction unit 801, configured to construct a fault simulation model of a mudstone smearing type fault to be drilled and trapped;

the scanning unit 802 is used for scanning the fault simulation model, generating surface data of a mudstone smearing type fault to be drilled and trapped, and sending the surface data to a closure quantitative analysis device for the trapped fault;

a closure quantitative analysis device 803 for a trap fault, which is used for reconstructing the received surface data to obtain a three-dimensional data volume; obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data volume; fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio; determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped; and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point.

In summary, in the system provided in the embodiment of the present invention, a three-dimensional data volume of a mudstone smear-type fault to be drilled and trapped is obtained, where the three-dimensional data volume is obtained by performing scanning reconstruction on a fault simulation model of the mudstone smear-type fault to be drilled and trapped; obtaining fracture zone mudstone smearing thickness and fault mud ratio of a plurality of sampling points according to the three-dimensional data volume; fitting the fracture zone mudstone smearing thickness and the fault mud ratio of the multiple sampling points, and determining a fitting coefficient of the fracture zone mudstone smearing thickness and the fault mud ratio; determining fracture zone mudstone smearing closing factors of a plurality of sampling points according to the fitting coefficient and the fault mud ratio of the plurality of sampling points of the mudstone smearing type fault to be drilled and trapped; and analyzing the closure of each sampling point of the mudstone smearing type fault to be drilled and trapped according to the mudstone smearing closure factor of the fractured zone of each sampling point. In the process, the method can analyze the sealing performance of the closed fault of the mudstone to be drilled, and in the analysis process, the fitting coefficient of the mudstone smearing thickness of the fractured zone and the ratio of the fault mud is determined, and the fitting coefficient can represent the effective smearing degree of the mudstone, so that the mudstone smearing sealing factor of the fractured zone is determined more accurately, and the accuracy of finally analyzing the sealing performance of each sampling point of the mudstone smearing type fault of the closed fault to be drilled is higher. In addition, the precision of the attribute information of the mudstone smearing type fault is improved by using the post-stack seismic data, the precision of the obtained three-dimensional data volume is high by using advanced means of physical simulation and industrial CT data quantitative acquisition and analysis, the problems of idealization of a calculation model, incomplete considered factors and low scientificity and accuracy in the existing fault closure analysis are solved quantitatively, scientific basis is provided for closure evaluation, leakage points are screened out by accurately evaluating the closure, the drilling is carried out to avoid investment risks, the method has good technical application prospect and economic benefit, the drilling success rate is improved, and the technical effect of evaluating the fault block trap according to the closure of the fault with higher precision is achieved.

An embodiment of the present application further provides a computer device, fig. 9 is a schematic diagram of the computer device in the embodiment of the present invention, the computer device is capable of implementing all steps in the method for quantitatively analyzing the closure of a trapping fault in the foregoing embodiment, and the electronic device specifically includes the following contents:

a processor (processor)901, a memory (memory)902, a communication Interface (Communications Interface)903, and a bus 904;

the processor 901, the memory 902 and the communication interface 903 complete mutual communication through the bus 904; the communication interface 903 is used for realizing information transmission among related devices such as server-side devices, detection devices, user-side devices and the like;

the processor 901 is configured to call the computer program in the memory 902, and when the processor executes the computer program, the processor implements all the steps in the method for quantitatively analyzing the closure of the trapped fault in the above embodiment.

Embodiments of the present application also provide a computer-readable storage medium, which can implement all steps in the method for quantitatively analyzing the closure of a trapping fault in the above-described embodiments, and the computer-readable storage medium stores thereon a computer program, which, when executed by a processor, implements all steps of the method for quantitatively analyzing the closure of a trapping fault in the above-described embodiments.

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

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

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

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

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A method for quantitatively analyzing the closure of a trapped fault, comprising:

2. The method for quantitatively analyzing the closure of a trap fault as set forth in claim 1, further comprising:

3. The method for quantitatively analyzing the closure of the trapped fault according to claim 1, wherein the obtaining of the fracture zone mudstone smear thickness and the fault mud ratio of a plurality of sampling points according to the three-dimensional data volume comprises:

4. The method for quantitatively analyzing the closure of the trapped fault as recited in claim 3, wherein the extracting fracture zone attribute information of the mudstone smear type fault from the three-dimensional data volume comprises:

and extracting the attribute information of the broken belt body.

5. The method for quantitatively analyzing the closure of a trapped fault as claimed in claim 1, characterized in that obtaining a three-dimensional data volume of a mudstone smear-type fault to be drilled for trapping comprises:

6. The method for quantitatively analyzing the closure of the entrapment fault as claimed in claim 5, wherein the configuration parameters of the physical simulation model of the entrapment to be drilled comprise one or any combination of model boundary, physical simulation model similarity ratio, physical simulation time length similarity ratio, simulated formation material and simulated mudstone material.

7. The method for quantitatively analyzing the closure of the entrapment fault of claim 5, wherein a difference method or a fitting method is adopted to carry out three-dimensional reconstruction on the surface data to obtain a three-dimensional data body of the mudstone smear type fault to be trapped by drilling.

8. The method for quantitatively analyzing the sealing property of the trapped fault according to claim 1, wherein the step of analyzing the sealing property of each sampling point of the mudstone-coated fault to be drilled and trapped according to the mudstone-coated sealing factor of the fractured zone of each sampling point comprises the following steps:

9. A closure quantitative analysis device for a trapped fault, comprising:

10. The closure profile quantitative analysis device of a entrapment fault of claim 9, wherein the third module is specifically configured to:

11. The occlusion fault closure quantitative analysis device of claim 9, wherein the second module is specifically configured to:

12. The closure profile quantitative analysis device of a entrapment fault of claim 11, wherein the second module is specifically configured to:

and extracting the attribute information of the broken belt body.

13. The occlusion fault closure quantitative analysis device of claim 9, wherein the first module is specifically configured to:

14. The apparatus for quantitative analysis of containment of trapped faults as claimed in claim 13, wherein the configuration parameters of the physical simulation model of the trapped fault to be drilled include one or any combination of model boundary, physical simulation model similarity ratio, physical simulation duration similarity ratio, simulated formation material and simulated mudstone material.

15. The occlusion layer seal quantitative analysis device of claim 13, wherein the first module is specifically configured to:

16. The closure profile quantitative analysis device of a entrapment fault of claim 9, wherein the fifth module is specifically configured to:

17. A system for closure quantitative analysis of a trapped fault, comprising: a fault simulation model construction unit, a scanning unit, and the closure quantitative analysis apparatus for a captive fault according to any one of claims 9 to 16,

18. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the method of any of claims 1 to 8 when executing the computer program.

19. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program for executing the method of any one of claims 1 to 8.