CN114562245A

CN114562245A - Fine seam control temporary plugging steering fracturing method

Info

Publication number: CN114562245A
Application number: CN202210212364.0A
Authority: CN
Inventors: 张佩波; 宋博
Original assignee: Bofeng Petroleum Technology Development Liaoning Co ltd
Current assignee: Bofeng Petroleum Technology Development Liaoning Co ltd
Priority date: 2022-03-04
Filing date: 2022-03-04
Publication date: 2022-05-31
Anticipated expiration: 2042-03-04
Also published as: CN114562245B

Abstract

The invention discloses a fine seam control temporary plugging steering fracturing method. The method comprises the following steps: when the target well is subjected to temporary plugging and steering fracturing, performing dynamic real-time monitoring on fracture extension by adopting microseism monitoring in each fracturing process of each fracturing section of the target well; when the fracture extension which is not beneficial to fracturing is monitored to occur in a certain stage of fracturing process of a certain fracturing section, a temporary plugging adjustment scheme is determined in real time, and after temporary plugging adjustment is performed on the fracturing section according to the temporary plugging adjustment scheme, subsequent fracturing is completed; the temporary plugging adjusting scheme comprises the delivery times of a temporary plugging agent, wherein the delivery times of the temporary plugging agent are determined based on the monitored fracture propagation characteristics of fracture extension which are not beneficial to fracturing.

Description

Fine seam control temporary plugging steering fracturing method

Technical Field

The invention belongs to the technical field of fracturing yield increase, and particularly relates to a fine crack control temporary plugging steering fracturing method.

Background

In recent years, the fracturing scale is developed towards the direction of large sand volume, large liquid volume and large discharge (industrialization), old wells in old areas of old oil fields are repeatedly fractured, new layer production increase and transformation, development and utilization of compact oil gas and shale oil gas resources, economic production and the like are taken as the basis and key for supporting the oil gas strategic safety. The concept of volume fracturing and fracture network fracturing guides the development direction of the fracturing technology.

However, the volume fracturing and fracture network fracturing process often has the problem that the fracturing fracture expansion cannot meet the design expectation of the fracturing process, which mainly shows a series of problems of unbalanced fracturing fracture expansion, poor fracture complexity, large modification difference between layers/clusters and the like, so that the volume fracturing and fracture network fracturing effects cannot meet the expectation, and the fracturing modification and production building effects are greatly influenced.

At present, a large number of temporary plugging fracturing process measures are carried out at home and abroad aiming at old layers of old wells, compact oil gas and shale oil gas, and the temporary plugging process implemented at present has a plurality of problems, wherein the common problems exist in the aspects of insufficient design quantitative calculation pertinence, poor diagnosis and adjustment in the construction process and insufficient analysis and evaluation after pressure.

How to better determine the using amount of the temporary plugging agent, how to diagnose and adjust the using amount of the temporary plugging agent and the injection mode of the temporary plugging agent according to the construction process, thereby realizing more precise crack extension control, achieving the purposes of improving the fracturing effect and improving the implementation level of the temporary plugging diversion process, and being the core problems which troubles the technical personnel in the field.

Disclosure of Invention

The invention aims to provide a fine crack control temporary plugging steering fracturing method which can finely control crack extension, thereby improving the fracturing effect and improving the implementation level of a temporary plugging steering process.

In order to achieve the above object, the present invention provides a fine crack control temporary plugging diversion fracturing method, wherein the method comprises:

when the target well is subjected to temporary plugging steering fracturing, performing dynamic real-time monitoring on fracture extension by adopting microseism monitoring in each fracturing stage of the target well in each fracturing process; when the fracture extension which is not beneficial to fracturing is monitored to occur in a certain stage of fracturing process of a certain fracturing section, a temporary plugging adjustment scheme is determined in real time, and after temporary plugging adjustment is performed on the fracturing section according to the temporary plugging adjustment scheme, subsequent fracturing is completed;

wherein the fracture propagation characteristics of fracture propagation that are not conducive to fracture propagation exhibit: the two wings of the fracture middle-stage fracture propagation are unbalanced, the fracture initial stage or middle-stage fracture lateral propagation is unbalanced, the fracture initial stage is laterally over-propagated, the natural fracture is pressed open in the fracturing process and is not extended, the natural fracture is pressed open in the fracturing initial stage and the natural fracture band is pressed open in the adjacent section of fracture, the extending net width of the fracture initial stage or middle-stage fracture is insufficient, the fracture response points in the fracturing middle stage are concentrated, or the fracture response points in the fracturing middle stage are scattered rarely;

the temporary plugging adjusting scheme comprises the delivering times of a temporary plugging agent (namely the times of temporary plugging), wherein the delivering times of the temporary plugging agent is determined based on the monitored fracture propagation characteristics unfavorable for fracture extension in fracturing;

(1) when the crack propagation characteristics show that two wings of crack propagation in the middle stage of fracturing are unbalanced, the temporary plugging agent is delivered in a concentrated mode;

the occurrence of the imbalance of the two wings of the crack extension is usually caused by the heterogeneity, perforation factors, in-situ stress factors and the like of a reservoir stratum, and the imbalance of the two wings of the crack extension is mostly shown by the characteristics that the crack extends excessively on one side and extends insufficiently on the other side, when the imbalance of the two wings of the crack extension is monitored by microseism in the middle stage of the fracturing of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of 1-time centralized delivery of the temporary plugging agent, so that the extension of one side of the advantage can be effectively limited, and meanwhile, the crack extension energy is distributed to the disadvantaged end;

(2) when the fracture expansion characteristic shows that the fracture at the initial stage of fracturing or the middle stage of fracturing is transversely expanded unevenly, the temporary plugging agent is delivered in a grading way for a plurality of times (more than or equal to 2 times);

the appearance of the transverse expansion unbalance of the cracks is usually caused by factors such as the heterogeneity, the three-dimensional stress difference, the weak surface seam difference, the inter-cluster fracture pressure difference and the like of a reservoir stratum, the characteristic that the pressing-open of the emergent hole clusters is unbalanced or part of the perforation clusters are not pressed open is frequently presented, when the transverse expansion unbalance of the cracks is monitored by micro-earthquakes in the early stage and the middle stage of the fracturing of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of delivering the temporary plugging agent for multiple times in a grading manner, the expansion of the preferentially pressed perforation clusters can be effectively limited, the distribution of fracturing fluid is adjusted and balanced, and other perforation clusters are effectively pressed open, so that each perforation cluster is relatively and uniformly expanded;

(3) when the crack propagation characteristics show the transverse excessive propagation of the initial crack of the fracturing, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times (more than or equal to 2 times);

the appearance of the transverse over-expansion of the crack is usually caused by the existence of natural crack or induced crack near a well bore, well cementation quality factors and the like, and the characteristic of over-expansion along the direction of the well bore or a parallel well bore is mostly presented, when the transverse over-expansion of the crack is monitored through micro-earthquake in the early stage of the fracturing of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of delivering the temporary plugging agent for once concentration or multiple times (more than or equal to 2 times) in a grading way, so that the transverse expansion dominant channel can be effectively temporarily plugged, and the crack is further extended to the depth;

(4) when the fracture propagation characteristics show that natural fractures are pressed open in the fracturing process and are not extended, the temporary plugging agent is delivered in a concentrated mode;

the occurrence of the pressed natural fracture is usually caused by local micro-fault or fracture development, and when the pressed natural fracture is detected to occur and not extend by micro-earthquake in the fracturing process of a fracturing section, temporary plugging adjustment is carried out by adopting a mode of 1 time of centralized delivery of temporary plugging agent;

(5) when the crack propagation characteristics show that natural cracks are pressed open at the initial stage of fracturing and the cracks of adjacent sections are pressed open in the natural crack zone, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times (more than or equal to 2 times);

the natural cracks are pressed open, the cracks of adjacent sections are also pressed open natural crack zones, the appearance of the natural crack zones is generally caused by crack extension communication, when the natural cracks are pressed open and the natural crack zones are pressed open by the cracks of the adjacent sections are monitored through microseisms in the initial stage of fracturing of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of delivering the temporary plugging agent for once concentration or multiple (more than or equal to 2 times) in a grading manner;

(6) when the crack propagation characteristics show insufficient extension net width of the crack at the initial stage or the middle stage of the fracture, the temporary plugging agent is delivered in a grading way for a plurality of times (more than or equal to 2 times);

the appearance of insufficient fracture extension net width is usually caused by factors such as poor reservoir brittleness, weak face joint failure and the like, and more cracks have the characteristic of single shape, when the defect of insufficient fracture extension net width is monitored by micro-earthquake in the early stage and the middle stage of the fracturing of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of delivering the temporary plugging agent for multiple times in a grading manner, so that the temporary plugging steering in the joints can be realized, branch fractures are generated, and the transverse control is strengthened;

(7) when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are concentrated, the temporary plugging agent is delivered in a grading way for multiple times (more than or equal to 2 times);

the concentrated appearance of the fracture response points is usually caused by factors of limited extension and expansion, insufficient net pressure, incapability of maintaining further effective extension of the fracture and the like, when the concentrated appearance of the fracture response points is monitored by microseism in the middle fracturing stage of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of delivering the temporary plugging agent for multiple times in a grading manner, so that the net pressure in the fracture can be effectively improved and adjusted, and the extension of the far well fracture is promoted;

(8) when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are sparsely dispersed, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times (more than or equal to 2 times);

the sparse dispersion of the crack response points leads to insufficient crack complexity, when the sparse dispersion of the crack response points is monitored through micro-earthquake in the middle stage of fracturing of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of one-time centralized delivery or multiple (more than or equal to 2 times) graded delivery of the temporary plugging agent, and the blocking of the superior crack channel and the opening of the blank area in the crack can be effectively realized.

In the fine crack control temporary plugging diversion fracturing method, each fracturing section of a target well refers to a fracturing section which is divided by adopting a staged fracturing modification process in the temporary plugging diversion fracturing process of the target well, and the fracturing section is usually determined by setting a staged packer in the fracturing process; the fracturing times of each fracturing section are the fracturing stages of the fracturing section, each fracturing of one fracturing section is each stage of the fracturing section, and the temporary plugging construction is usually carried out between two stages of fracturing of one fracturing section.

In the fine crack temporary blocking control steering fracturing method, in the process of carrying out dynamic real-time monitoring on crack extension by adopting microseism monitoring, whether crack extension dynamic state shows unbalanced lateral expansion of cracks, whether crack lateral over-expansion is shown, whether fracture natural crack is shown and extends unfavorably, whether fracture natural crack is shown and natural crack band is already shown, and whether crack extension net width is insufficient is monitored at the initial stage of fracturing; monitoring whether fracture expansion dynamic state shows that two wings of the fracture are unbalanced, whether the fracture is transversely expanded or not, whether the fracture is naturally fractured and is not extended, whether the fracture is extended with insufficient net width, whether the fracture response points are concentrated or not, and whether the fracture response points are sparsely dispersed in the middle stage of fracturing; the fracture propagation dynamics were monitored late in the fracture for the appearance of fracturing natural fractures and unfavorable extensions.

In the fine crack control temporary blocking steering fracturing method, the pre-fracturing stage refers to a stage 1/3 from the beginning of fracturing of a certain stage of fracturing to the stage of total fracturing design fluid volume (sum of the design dosage of the pad fluid and the design dosage of the sand carrier fluid) of the fracturing stage, the middle fracturing stage refers to a stage 1/3 from the stage of total fracturing design fluid volume (sum of the design dosage of the pad fluid and the design dosage of the sand carrier fluid) of the fracturing stage exceeding the stage of fracturing of the fracturing stage in the certain fracturing of the fracturing stage to the stage 3/2, and the post-fracturing stage refers to a stage 2/3 from the stage of total fracturing design fluid volume (sum of the design dosage of the pad fluid and the design dosage of the sand carrier fluid) of the fracturing stage exceeding the stage of the fracturing stage in the certain fracturing stage to the stage of total fracturing design fluid volume (sum of the design dosage of the pad fluid and the design dosage of the sand carrier fluid) of the fracturing stage 3/4 .

In the fine crack temporary plugging control turning fracturing method, the imbalance of two wings in crack expansion is judged according to the conventional mode in the field, and the imbalance of two wings in crack expansion is judged when the extension length difference of the two wings is more than 20 percent; the transverse expansion imbalance of the cracks is judged according to the conventional mode in the field, and usually, the transverse coverage area of the crack monitoring event point is less than 60 percent of the fracturing layer section to judge that the transverse expansion imbalance of the cracks is caused; judging the transverse excessive expansion of the fracture according to a conventional mode in the field, and judging that the transverse coverage of the fracture event point along the shaft is more than 20% of the section length; lateral over-propagation of the crack; the fracture is broken through and unfavorable extension is judged according to the conventional mode in the field, generally, fracture event points are mainly concentrated on the broken natural fractures, and the broken natural fractures and the unfavorable extension are judged if the number of event points in a transformation area is small; the insufficient width of the fracture extension net can be judged according to the conventional mode in the field, and the insufficient width of the fracture extension net is usually judged when the coverage area of the fracture event point is less than 60% of the length of the fracturing section; judging the crack response points in a centralized manner according to a conventional mode in the field, wherein usually the crack event points are distributed in a centralized manner in an area with the designed crack length of 50 percent to judge that the crack response points are centralized; the sparse dispersion of the fracture response points can be judged according to the conventional mode in the field, and the sparse dispersion of the fracture response points is judged when the number of the fracture event points is smaller than 50% of the number of the same-period fracture event points of the adjacent fracturing sections.

In the fine crack control temporary blocking steering fracturing method, when two or more characteristics of uneven expansion wings of a middle-stage fracturing crack, uneven transverse expansion of an initial fracturing crack or a middle-stage fracture, uneven transverse over-expansion of the initial fracturing crack, uneven pressing of a natural crack in a fracturing process, natural crack pressing of the initial fracturing crack and natural crack belt pressing of adjacent sections of the crack are monitored, insufficient net width of the initial fracturing crack or the middle-stage fracture expansion, concentrated response points of the middle-stage fracturing crack and rare dispersion of response points of the middle-stage fracturing crack are monitored, which characteristic is the most important characteristic, namely the crack expansion characteristic of the crack which is not beneficial to fracture expansion; and subsequently determining the delivery times of the temporary plugging agent in the temporary plugging adjustment scheme based on the most main characteristic.

In the fine crack temporary blocking control steering fracturing method, preferably, when the crack propagation characteristics show that the fracture is transversely unevenly propagated in the early stage or the middle stage of fracturing, the temporary blocking agent is delivered by 3-4 times of grading.

In the fine crack control temporary blocking steering fracturing method, preferably, when the crack propagation characteristics show the transverse excessive propagation of the crack in the initial stage of fracturing, the temporary blocking agent is delivered for 1-2 times.

In the fine crack control temporary blocking steering fracturing method, preferably, when the crack propagation characteristics show that the natural crack is pressed open at the early stage of fracturing and the crack of the adjacent section presses open the natural crack belt, the temporary blocking agent is delivered for 1-2 times.

In the fine crack control temporary blocking steering fracturing method, preferably, when the crack propagation characteristics show insufficient fracture extending net width in the early stage or the middle stage of fracturing, the temporary blocking agent is delivered in 2-4 times of grading.

In the fine crack control temporary blocking steering fracturing method, preferably, when the crack propagation characteristics show that the response points of the crack are concentrated in the middle stage of fracturing, the temporary blocking agent is delivered by 2-3 times in a grading manner.

In the fine crack control temporary blocking steering fracturing method, preferably, when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are rarely dispersed, the temporary blocking agent is delivered by 1-2 times of grading.

In the above fine crack temporary control steering fracturing method, preferably, the method further comprises:

when the target well is subjected to temporary plugging and steering fracturing, monitoring fracturing construction dynamic data in each fracturing process of each fracturing section of the target well; fitting in real time by combining the fracturing construction dynamic data and the microseism monitoring data to realize the inversion of the fracture form;

more preferably, when the temporary plugging adjustment scheme is determined, the design dosage of the temporary plugging agent delivered each time is determined according to the crack morphology obtained by inversion; in the preferred technical scheme, the fitting and the microseism monitoring means are combined, so that the on-site real-time adjustment is more targeted;

more preferably, in the process of combining the dynamic data of the fracturing construction and the microseism monitoring data to carry out real-time fitting and realizing the inversion of the fracture morphology,

not only is the crack form, pressure distribution, fluid distribution and stress distribution in the model described, but also the variable quantity of solid deformation and the variable quantity of physical property parameters in the model space are automatically updated based on the evolution of the crack form, and the automatic division with large numerical simulation grids is carried out again.

In the above-mentioned fine seam temporary plugging control steering fracturing method, preferably, the temporary plugging adjustment scheme includes a design dosage of the temporary plugging agent delivered each time, and the design dosage of the temporary plugging agent delivered each time is determined based on the following formula:

when the target temporary plugging crack is a horizontal crack,

M_D＝K·π·W_f·[(R+Δd)²-R²]·ρ_D

M_Dthe unit kg of the temporary plugging agent is the design dosage for each delivery; k is a radial expansion coefficient, and the unit is dimensionless; w_fThe width of the target temporary plugging crack is m; delta d is the target thickness of the temporary plugging agent filter cake in m; rho_DFor temporary blocking of the density of the filter cake, units kg/m³(ii) a R is the radial expansion radius (namely the distance between the target temporary plugging position and the central axis of the shaft) of the target steering position, and is unit m;

when the target temporarily blocks the vertical seam of the crack,

M_D＝π·H·(d·Δd+Δd²)·ρ_D·α·β+π·H·(d·Δd+Δd²)·ρ_D·α

M_Dthe unit kg of the temporary plugging agent is the design dosage for each delivery; h is the seam height of the target temporary plugging crack, and the unit is m; d is the width of the target temporary plugging crack in unit m; delta d is the target thickness of the temporary plugging agent filter cake in m; rho_DFor temporary blocking of the density of the filter cake, units kg/m³(ii) a Beta is a permeability variation coefficient, and the unit is dimensionless; alpha is a crack factor, and the unit is dimensionless.

In the above-described fine crack temporary plugging controlled turning fracturing method, preferably, the method further comprises:

before the target well is subjected to temporary plugging diversion fracturing, a temporary plugging diversion fracturing scheme is formulated to guide the target well to be subjected to temporary plugging diversion fracturing;

wherein, formulate target well temporary plugging diversion fracturing scheme and include:

performing geological modeling and fracturing modeling on a target well;

carrying out numerical simulation on fracture initiation extension and perforation cluster extension on the basis of geological modeling and fracturing modeling;

carrying out an object model experiment to determine the type of the temporary plugging agent;

combining the numerical simulation result and the physical model experiment result to formulate a temporary plugging diversion fracturing scheme for guiding a target well to perform temporary plugging diversion fracturing;

in one embodiment, the method for creating the temporary plugging diversion fracturing plan of the target well comprises the following steps:

collecting geological data, single well ground stress data and rock mechanics data of a target well, and carrying out geological modeling and fracturing modeling on the target well based on the collected data;

on the basis of modeling, carrying out numerical simulation on fracture initiation extension and perforation cluster extension under different temporary plugging conditions;

carrying out a physical model experiment based on the reservoir temperature, pressure and formation fluid characteristics of a target well, and carrying out indoor evaluation and optimization on the temporary plugging agent so as to determine the type of the temporary plugging agent;

formulating a temporary plugging diversion fracturing scheme based on the numerical simulation result and the physical model experiment result to guide a target well to perform temporary plugging diversion fracturing;

the geological modeling and the fracturing modeling are carried out by adopting a conventional mode in the field, the physical modeling experiment is carried out by adopting a conventional mode in the field, and the temporary plugging diversion fracturing scheme is appointed to be carried out by adopting a conventional mode in the field;

in the preferred technical scheme, the established target well temporary plugging diversion fracturing scheme generally comprises a plurality of fracturing sections of the target well, each fracturing section is subjected to several stages of fracturing respectively, fracturing construction parameters (including the type of fracturing fluid, the using amount of the fracturing fluid, the pumping parameters of the fracturing fluid and the like) of each stage of fracturing of each fracturing section, temporary plugging agent injection construction parameters (including the type of temporary plugging agent, the using amount of the temporary plugging agent, the pumping parameters of the temporary plugging agent and the like) between each stage of fracturing and the like.

In the above-mentioned fine-seam temporary plugging control steering fracturing method, preferably, each time the temporary plugging agent is delivered, the temporary plugging agent is delivered according to the designed amount, and then the following steps are further performed:

when the plane steering needs to be realized after the temporary plugging agent is injected, judging whether the pressure difference formed after the temporary plugging agent is injected is larger than the difference value between the maximum principal stress and the minimum principal stress of the stratum or not and the difference value between the fracture pressure of the block and the opening pressure of the previous seam or not, finishing the delivery of the temporary plugging agent if the pressure difference formed after the temporary plugging agent is injected is larger than the difference value between the maximum principal stress and the minimum principal stress of the stratum or the difference value between the fracture pressure of the block and the opening pressure of the previous seam or not, or further injecting the temporary plugging agent until the pressure difference formed after the temporary plugging agent is larger than the difference value between the maximum principal stress and the minimum principal stress of the stratum or larger than the difference value between the fracture pressure of the block and the opening pressure of the previous seam;

and when the longitudinal steering is required to be realized after the temporary plugging agent is injected, judging whether the pressure difference formed after the temporary plugging agent is injected is greater than the minimum main stress on the section and the difference between the fracture pressure of the block and the opening pressure of the previous seam, finishing the delivery of the temporary plugging agent if the pressure difference formed after the temporary plugging agent is injected is greater than the minimum main stress on the section and is greater than the difference between the fracture pressure of the block and the opening pressure of the previous seam, and otherwise, further injecting the temporary plugging agent until the pressure difference formed after the temporary plugging agent is injected is greater than the minimum main stress on the section and is greater than the difference between the fracture pressure of the block and the opening pressure of the previous seam.

after each stage of fracturing of each fracturing section of the target well is finished, analyzing after fracturing respectively, summarizing the relevance and regularity of the temporary plugging parameters and the implementation effect,

in the preferred embodiment, the post-fracturing analysis may be performed in a manner conventional in the art, for example, using a combination of fracture construction data analysis and test data analysis to perform post-fracturing analysis including dynamic fitting of fracture construction data, pump-down pressure drop test analysis, long-term production data flow field evolution analysis.

after the temporary plugging, steering and fracturing of the target well are completed, carrying out productivity fitting;

in the preferred embodiment, the productivity fitting can be performed by a conventional method in the art, for example, by a comprehensive method of a fracturing well test dynamic interpretation method and numerical simulation dynamic fitting, a numerical range of key model parameters of a fracturing well is determined qualitatively by the fracturing well test dynamic interpretation method, upper and lower limits of the model parameters are determined according to flow field evolution to be used as parameter value taking domains of a quantitative productivity fitting model, and then parameter inversion is performed in the parameter domains by a constraint optimization method through the numerical simulation dynamic fitting method to predict future yield.

In the fine-seam temporary plugging control diversion fracturing method, the temporary plugging agent used is selected from temporary plugging agents commonly used in the field, and preferably, the temporary plugging agent used meets at least one of the following conditions:

(1) comprises a plurality of temporary plugging materials;

(2) high temperature resistance;

(3) the bearing performance is good;

(4) the degradation time is controllable;

(5) no harm to the reservoir;

the condition is satisfied, and the application of reservoir fracturing modification of the high-temperature deep well is facilitated.

The inventor optimizes the temporary plugging diversion fracturing process, and realizes more precise crack extension control by additionally arranging a temporary plugging adjustment scheme according to microseism monitoring in the temporary plugging diversion fracturing process, thereby achieving the purposes of improving the fracturing effect and improving the implementation level of the temporary plugging diversion process. The fine crack control temporary blocking steering fracturing method provided by the invention is suitable for old well fracturing and is beneficial to realizing the development of residual oil gas of an old well, the fracturing effect is excellent, the aims of maximizing the fracturing modification volume and maximizing the fracture complexity degree are taken as targets, and the modification volume realized by the fine crack control temporary blocking steering fracturing method provided by the invention is more than 1.5 times of that of conventional fracturing.

Drawings

FIG. 1 is a schematic diagram of temporary plugging fracturing in a multistage fracture.

Fig. 2A is a schematic diagram of repeated fracturing of a high water content old well.

Fig. 2B is a schematic diagram of repeated fracturing of medium and high water wells.

Fig. 3 is a schematic flow chart of the fine fracture control temporary plugging diversion fracturing method provided in example 1.

Fig. 4 is a layout diagram of the on-site fracturing equipment in example 1.

FIG. 5A is a graph comparing the effects of fracturing a natural fracture and the occurrence of unfavorable propagation before and after a temporary plugging adjustment construction in the fracturing process of example 1.

FIG. 5B is a comparison graph of the effects before and after the temporary plugging adjustment construction is performed in case of uneven crack propagation at the middle stage of fracturing in example 1.

Fig. 5C is a comparison graph of the effects before and after the temporary plugging adjustment construction is performed when the fracture response points in the middle stage of fracturing are concentrated in example 1.

FIG. 5D is a graph comparing the effects before and after the temporary plugging adjustment construction is performed in case of the lateral over-propagation of the fracture at the initial stage of fracturing in example 1.

FIG. 6A is a three-dimensional porosity model of example 1.

FIG. 6B is a three-dimensional permeability model diagram of example 1.

Fig. 6C is a three-dimensional saturation model diagram in example 1.

FIG. 6D is a diagram of a model of a natural fracture in example 1.

FIG. 6E is a diagram of an artificial fracture model in example 1.

Fig. 6F is a north-south three-dimensional sand body model diagram in example 1.

FIG. 6G is a diagram of a three-dimensional sand body model in the east-west direction in example 1.

FIG. 7 is a chart of productivity fit results.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below in connection with preferred embodiments. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.

The temporary blocking and diverting fracturing of each fracturing section is usually implemented by temporary blocking and fracturing or repeated fracturing in a multi-stage fracture, the main fracture, branch fracture, secondary branch fracture and the like can be formed by the temporary blocking and fracturing principle in the multi-stage fracture as shown in figure 1, and the repeated fracturing principle can form repeated fracturing fracture, old fracture, diverting fracture, secondary fracture and the like as shown in figures 2A and 2B, and because the fracturing effect cannot reach the expected phenomenon often occurs in the temporary blocking and diverting fracturing of fracturing complexity, the fracturing transformation and production effect are greatly influenced.

In order to realize fine crack control in the temporary plugging diversion fracturing process and achieve the purposes of improving the fracturing effect and improving the implementation level of the temporary plugging diversion process, a specific implementation mode of the invention provides a fine crack control temporary plugging diversion fracturing method, which comprises the following steps:

when the target well is subjected to temporary plugging and steering fracturing, performing dynamic real-time monitoring on fracture extension by adopting microseism monitoring in each fracturing process of each fracturing section of the target well; when the fracture extension which is not beneficial to fracturing is monitored to occur in a certain stage of fracturing process of a certain fracturing section, a temporary plugging adjustment scheme is determined in real time, and subsequent fracturing is completed after temporary plugging adjustment is performed on the fracturing section according to the temporary plugging adjustment scheme;

wherein the temporary plugging adjustment scheme comprises the delivery times of the temporary plugging agent (namely the times of temporary plugging), and the delivery times of the temporary plugging agent are determined based on the monitored fracture propagation characteristics of fracture extension which are not beneficial to fracturing:

(1) when the crack propagation characteristics show that the two wings of the crack are unbalanced during the middle stage of the fracture propagation, the temporary plugging agent is delivered in a concentrated mode;

(6) when the crack propagation characteristics show that the extension net width of the crack at the initial stage or the middle stage of the fracturing is insufficient, the temporary plugging agent is delivered in a grading way for multiple times (more than or equal to 2 times);

the insufficient width of the fracture extending net is usually caused by factors such as poor brittleness of a reservoir stratum, non-development of weak face seams and the like, and mostly presents the characteristic of single fracture form, when the insufficient width of the fracture extending net is monitored by micro-earthquakes in the early stage and the middle stage of fracturing of a fracturing section, the temporary plugging adjustment is carried out by adopting a mode of delivering the temporary plugging agent in a grading manner for multiple times, so that the temporary plugging steering in seams can be realized, branch fractures are generated, and the transverse control is strengthened;

Further, when the fracture expansion characteristics show that the fracture transversely expands unevenly in the early stage or the middle stage of the fracturing, the temporary plugging agent is delivered in 3-4 times in a grading manner.

Further, when the fracture propagation characteristics show the fracture transverse over-propagation in the initial stage of fracturing, the temporary plugging agent is delivered for 1-2 times.

Further, when the fracture propagation characteristics show that the natural fracture is pressed open at the early stage of fracturing and the fracture of the adjacent section presses open the natural fracture belt, the temporary plugging agent is delivered for 1-2 times.

Further, when the fracture propagation characteristics show insufficient fracture extension net width in the early stage or the middle stage of fracturing, the temporary plugging agent is delivered by 2-4 times in a grading manner.

Further, when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are concentrated, the temporary plugging agent is delivered in a grading mode for 2-3 times.

Further, when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are rarely dispersed, the temporary plugging agent is delivered by grading for 1-2 times.

Further, the method further comprises:

furthermore, when a temporary plugging adjustment scheme is determined, the design dosage of the temporary plugging agent in each delivery is determined according to the crack form obtained by inversion; in the preferred technical scheme, the fitting and the microseism monitoring means are combined, so that the on-site real-time adjustment is more targeted;

furthermore, in the process of combining the dynamic data of the fracturing construction and the microseism monitoring data to carry out real-time fitting and realizing the inversion of the fracture form,

the method not only describes the crack form, pressure distribution, fluid distribution and stress distribution in the model, but also automatically updates the variation of solid deformation and the variation of physical property parameters in the model space based on the evolution of the crack form, and repeatedly performs automatic division with large numerical simulation grids.

Further, the temporary plugging adjustment scheme comprises the design dosage of the temporary plugging agent delivered each time, and the design dosage of the temporary plugging agent delivered each time is determined based on the following formula:

when the target temporary plugging crack is a horizontal crack,

M_D＝K·π·W_f·[(R+Δd)²-R²]·ρ_D

M_Dthe unit kg of the temporary plugging agent is the design dosage for each delivery; k is a radial expansion coefficient, and the unit is dimensionless; w_fThe width of the target temporary plugging crack is m; delta d is the target thickness of the temporary plugging agent filter cake in m; rho_DFor temporary blocking of the density of the filter cake, units kg/m³(ii) a R is the radial expansion radius (namely the distance between the temporary target plugging position and the central axis of the shaft) of the target steering position in unit m;

when the target temporary plugging crack is a vertical crack,

M_D＝π·H·(d·Δd+Δd²)·ρ_D·α·β+π·H·(d·Δd+Δd²)·ρ_D·α

M_Dthe unit kg is the designed dosage of the temporary plugging agent for each delivery; h is the joint height of the target temporary plugging crack, and the unit is m; d is the width of the target temporary plugging crack in unit m; delta d is the target thickness of the temporary plugging agent filter cake in m; rho_DFor temporary blocking of the density of the filter cake, units kg/m³(ii) a Beta is a permeability variation coefficient, and the unit is dimensionless; alpha is a crack factor, and the unit is dimensionless.

Further, the method further comprises:

performing geological modeling and fracturing modeling on a target well;

further, the developing a target well diverting fracturing plan includes:

collecting geological data, single-well ground stress data and rock mechanics data of a target well, and performing geological modeling and fracturing modeling on the target well based on the collected data;

Further, when the temporary plugging agent is delivered every time, the temporary plugging agent is delivered according to the designed dosage and then the following steps are further carried out:

when the plane steering is required to be realized after the temporary plugging agent is injected, judging whether the pressure difference formed after the temporary plugging agent is injected is greater than the difference between the maximum principal stress and the minimum principal stress of the stratum or not and whether the pressure difference formed after the temporary plugging agent is injected is greater than the difference between the fracture pressure of the block and the opening pressure of the previous seam or not, if the pressure difference formed after the temporary plugging agent is injected is greater than the difference between the maximum principal stress and the minimum principal stress of the stratum and is greater than the difference between the fracture pressure of the block and the opening pressure of the previous seam, finishing the delivery of the temporary plugging agent, otherwise, further injecting the temporary plugging agent until the pressure difference formed after the temporary plugging agent is injected is greater than the difference between the maximum principal stress and the minimum principal stress of the stratum and is greater than the difference between the fracture pressure of the block and the opening pressure of the previous seam;

Further, the method also includes:

in the preferred embodiment, post-fracturing analysis may be performed in a manner conventional in the art, for example, using a combination of fracture construction data analysis and test data analysis, including dynamic fracturing construction data fitting, pump down pressure drop test analysis, long term production data flow field evolution analysis.

Further, the method further comprises:

in the preferred embodiment, the productivity fitting can be performed in a conventional manner in the field, for example, a comprehensive method of fracturing well test dynamic interpretation method and numerical simulation dynamic fitting is adopted, the numerical range of key model parameters of a fracturing well is determined qualitatively by the fracturing well test dynamic interpretation method, the upper and lower limits of the model parameters are determined according to flow field evolution to serve as parameter value taking ranges of a quantitative productivity fitting model, and then a constraint optimization method is used for performing parameter inversion and predicting future yield in the parameter ranges by the numerical simulation dynamic fitting method.

Further, the temporary plugging agent used satisfies at least one of the following conditions:

(1) comprises a plurality of temporary plugging materials;

(2) high temperature resistance;

(3) the bearing performance is good;

(4) the degradation time is controllable;

(5) no harm to the reservoir.

Further, the fracturing construction steps are explained by taking fracturing of a certain section of a target well as an example:

(1) completing the perforation bridge plug connection of the fracturing section according to the design;

(2) throwing a soluble plugging ball on the ground, and plugging the fractured section when the ball is seated on the bridge plug;

(3) performing first-stage sand fracturing construction;

(4) adding the temporary plugging agent by a special plugging device, after plugging, delivering the temporary plugging agent by a constant displacement pump, observing pressure response after the temporary plugging agent is put in place, and after the pressure response meets the requirement, completing the delivery of the temporary plugging agent;

(5) carrying out next-stage sand adding construction;

(6) repeating the steps (4) to (5) until the transformation is finished;

the method comprises the following steps of carrying out fracture extension dynamic real-time monitoring and fracture construction dynamic data monitoring by adopting micro-seismic monitoring in a fracturing process, and carrying out real-time fitting by combining the monitored fracture construction dynamic data and the micro-seismic monitoring data to realize inversion of fracture morphology in a temporary plugging diversion fracturing process; when it is monitored that fracture extension which is not beneficial to fracturing is generated in the fracturing section in a certain stage of fracturing process, the fracturing construction is analyzed in real time, a temporary plugging adjustment scheme is determined, and after the temporary plugging adjustment construction is performed on the fracturing section according to the temporary plugging adjustment scheme, subsequent temporary plugging diversion fracturing construction is performed;

further, when the target well is a casing change well, the fine seam control temporary plugging diversion fracturing construction of the target well comprises the following steps:

(1) opening temporary plugging fracturing section perforation clusters in a one-time and all-shot mode;

(2) performing first-stage sand fracturing construction;

(3) adding the temporary plugging agent by a special plugging device, after plugging, delivering the temporary plugging agent by a constant displacement pump, observing pressure response after the temporary plugging agent is put in place, and after the pressure response meets the requirement, completing the delivery of the temporary plugging agent;

(4) carrying out next-stage sand adding construction;

(5) repeating the steps (3) to (4) until the transformation is finished;

the method comprises the following steps of performing fracture extension dynamic real-time monitoring and fracture construction dynamic data monitoring by adopting microseism monitoring in a fracturing process, and performing real-time fitting by combining the monitored fracture construction dynamic data and microseism monitoring data to realize inversion of fracture forms in a temporary plugging diversion fracturing process; and when the fracture extension which is not beneficial to fracturing is monitored in a certain stage of fracturing process, determining a temporary plugging adjustment scheme in real time, performing temporary plugging adjustment construction on the fracturing section according to the temporary plugging adjustment scheme, and then performing subsequent temporary plugging diversion fracturing construction.

Example 1

The embodiment provides a fine crack control temporary plugging diversion fracturing method, as shown in fig. 3, the method comprises the following steps:

step 1: collecting data of the target well;

and collecting geological data, single well ground stress data and rock mechanics data of the target well, and collecting adjacent well fracturing construction parameters and microseism detection data.

Step 2: geological modeling and fracturing modeling;

and (3) carrying out geological modeling and fracturing modeling on the target well based on the data collected in the step (1).

And step 3: on the basis of modeling, carrying out numerical simulation on fracture initiation extension and perforation cluster extension under different temporary plugging conditions;

and determining proper temporary plugging conditions including the dosage of the temporary plugging agent by carrying out numerical simulation on fracture initiation extension and perforation cluster extension under different temporary plugging conditions.

And 4, step 4: and carrying out a physical model experiment based on the reservoir temperature, pressure and formation fluid characteristics of the target well, and carrying out indoor evaluation and optimization on the temporary plugging agent so as to determine the type of the temporary plugging agent.

And 5: formulating a temporary plugging diversion fracturing scheme of the target well based on the numerical simulation result and the physical model experiment result;

and 6: performing temporary plugging, steering and fracturing construction on a target well according to a temporary plugging, steering and fracturing scheme, performing real-time monitoring on fracture extension dynamic and fracturing construction dynamic data by adopting micro-seismic monitoring in the construction process, and performing real-time fitting by combining the monitored fracturing construction dynamic data and the micro-seismic monitoring data to realize inversion of fracture morphology in the temporary plugging, steering and fracturing process; in the temporary plugging diversion fracturing construction process, when the fracture extension which is not beneficial to fracturing is monitored to occur in a certain stage of fracturing process of a certain fracturing section, a temporary plugging adjustment scheme is determined in real time, and subsequent temporary plugging diversion fracturing construction is carried out after temporary plugging adjustment construction is carried out on the fracturing section according to the temporary plugging adjustment scheme;

wherein fracture propagation characteristics of fracture propagation that are not conducive to fracture propagation exhibit: the method comprises the following steps of unbalanced two wings of fracture middle-stage fracture expansion, unbalanced transverse expansion of fracture early-stage or middle-stage fractures, transverse over-expansion of fractures at the fracture early-stage, pressing open of natural fractures in the fracturing process and unfavorable extension, pressing open of natural fractures at the fracture early-stage and pressing open of natural fracture belts of adjacent sections, insufficient extension net width of fractures at the fracture early-stage or middle-stage, centralized response points of fractures at the fracture middle stage, or rare dispersion of response points of fractures at the fracture middle stage;

wherein, the temporary blocking adjustment scheme comprises the delivery times of the temporary blocking agent and the design dosage of the temporary blocking agent delivered every time;

the number of times of delivering the temporary plugging agent is determined based on the monitored crack propagation characteristics unfavorable for fracture extension in fracturing:

when the crack propagation characteristics show that the two wings of the crack are unbalanced during the middle stage of the fracture propagation, the temporary plugging agent is delivered in a concentrated mode;

when the fracture expansion characteristic shows that the fracture at the initial stage of fracturing or the middle stage of fracturing is transversely expanded unevenly, the temporary plugging agent is delivered in a grading way for a plurality of times (more than or equal to 2 times);

when the crack propagation characteristics show that the crack is transversely excessively propagated in the initial stage of fracturing, the temporary plugging agent is delivered in a concentrated manner once or in a grading manner for multiple times (more than or equal to 2 times);

when the fracture propagation characteristics show that natural fractures are pressed open in the fracturing process and are not extended, the temporary plugging agent is delivered in a concentrated mode;

when the crack propagation characteristics show that a natural crack is pressed open at the initial stage of fracturing and a natural crack zone is pressed open by a crack at an adjacent section, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times (more than or equal to 2 times);

when the crack propagation characteristics show insufficient extension net width of the crack at the initial stage or the middle stage of the fracture, the temporary plugging agent is delivered in a grading way for a plurality of times (more than or equal to 2 times);

when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are concentrated, delivering the temporary plugging agent for multiple times (more than or equal to 2 times) in a grading way;

when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are sparsely dispersed, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times (more than or equal to 2 times);

the design dosage of the temporary plugging agent for each delivery is determined based on the following formula:

when the target temporary plugging crack is a horizontal crack,

M_D＝K·π·W_f·[(R+Δd)²-R²]·ρ_D

when the target temporary plugging crack is a vertical crack,

M_D＝π·H·(d·Δd+Δd²)·ρ_D·α·β+π·H·(d·Δd+Δd²)·ρ_D·α

M_Dthe unit kg of the temporary plugging agent is the design dosage for each delivery; h is the seam height of the target temporary plugging crack, and the unit is m; d is the width of the target temporary plugging crack in unit m; delta d is the target thickness of the temporary plugging agent filter cake in m; rho_DFor temporary blocking of the density of the filter cake, units kg/m³(ii) a Beta is the coefficient of variation of permeability, and the unit is dimensionless; alpha is a crack factor, and the unit is dimensionless;

wherein, in the temporary plugging diversion fracturing work progress and the temporary plugging adjustment work progress, when carrying out temporary plugging agent delivery at every turn, the temporary plugging agent is further carried out the following steps after delivering according to the design quantity:

Specifically, in the present embodiment, the temporary plugging diversion fracturing construction of a target well includes:

A. preparation before construction:

the oil testing and production testing team is responsible for fracturing the wellhead and preparing the connection of the pipe column:

(1) arranging roads and well sites to meet construction requirements;

(2) tripping the tubular column; wherein, the well head needs to be equipped with a well killing controller to prevent the falling objects and blowout in the well, and the oil pipe is thoroughly flushed by a boiler before the pipe column is put down;

(3) installing a fracturing manifold in cooperation with a fracturing team; the fracturing manifold adopts an 8-branch manifold, so that the construction requirement of large displacement is met;

(4) a liquid receiving platform and a dirty oil and sewage recovery (reinjection) device;

(5) assembling a Christmas tree at a wellhead;

(6) preparing ground and in-well tools such as a gate, a short section, a variable buckle joint and the like with pressure resistance of 90 MPa;

(7) preparing one cement truck and 24m of clean water³；

(8) Connecting a well backwashing pipeline before fracturing;

(9) in the process of liquid drainage and yield determination, two returned liquid samples are collected in an encrypted manner, and a fixed time is provided every day for analysis;

a fracturing team prepares for:

(1) anti-seepage cloth is laid in the fracturing construction area and the liquid distribution area to prevent various liquid and solid raw materials from falling to the ground;

(2) determining the fracturing construction scale, the fracturing construction process and the liquid preparation scheme;

(3) preparing a fracturing fluid;

(4) preparing a temporary plugging agent;

(5) preparing a fracturing truck set; the fracturing truck set meets the design requirement of water horsepower, and the pump cannot be stopped in the construction process;

(6) preparing for instrument metering (pressure, sand ratio and discharge curve) in fracturing construction;

(7) preparing for testing the pressure of the instant stop pump before and after fracturing;

(8) preparing a fracturing fluid storage tank (comprising a slickwater liquid storage tank, an active water liquid storage tank and a clear water liquid storage tank), a soft tank (used for containing a temporary plugging agent) and other liquid preparation devices; the liquid preparation devices such as fracturing fluid storage tanks, soft tanks and the like need to be washed clean in advance;

(9) placing the train sets according to a site fracturing equipment placing diagram (see figure 4); 6 fracturing pump trucks, 8m are required³One set of/min liquid preparation device, which comprises 3 slickwater liquid storage tanks (30-40 m)³One), 2 active water storage tanks (30 m)³One) 1 clear water storage tank (30 m)³One) 1 soft body can (400 m)³A/one).

Production operation and coordination unit:

(1) preparing two water source wells within 5km, and the liquid supply flow rate is 100m³More than one hour;

(2) responsible for contacting and designating roads;

(3) the method is responsible for expropriating the designated fracturing land;

(4) and coordinating the safe and environment-friendly communication and connection in the field of 1 km.

B. Construction is preceding to constructor technical bottom of handing over

(1) Each post needs to check the own equipment carefully to ensure the integrity;

(2) cleaning the liquid tank before liquid preparation and loading;

(3) when the liquid is prepared on site, various additives can be added into the cross-linking liquid according to the formula proportion;

(4) performing a crosslinking test before pressing, and recording the crosslinking condition;

(5) before construction, the fractured well mouth and the ground pipeline are carefully checked, and check records are recorded;

(6) construction is carried out according to design, and no puncture and no leakage are ensured;

(7) when the fracturing construction is carried out, the shaft is filled with liquid with small discharge capacity;

(8) if sand blockage occurs in the sand adding process, immediately starting a pump truck to wash the sand to clear water;

(9) if the designed sand amount cannot be achieved due to special conditions, the sand amount is required to be agreed by contacting a target well manager;

(10) the violation operation is strictly prohibited, the safety construction is paid attention to, the environment-friendly work is enhanced, and the personal injury is avoided;

(11) strictly forbidding running, leakage and leakage in the fracturing construction, and strictly forbidding putting fracturing sand and fracturing fluid randomly;

(12) strictly forbidding personnel to enter a high-pressure area during construction;

(13) designing a cross-bottom and performing the signing procedure.

C. The construction steps are as follows:

(1) connecting a ground manifold;

(2) circulating on the ground, detecting the puncture and connection conditions and checking and accepting to be qualified;

(3) wellhead and surface pipeline pressure testing (low pressure and high pressure pipelines): the pressure test of the ground pipeline and the gate is 70MPa, the stability is 10min, no puncture and no leakage are qualified, and the pressure test adopts clean water to avoid the pipeline puncture and leakage from polluting the ground;

(4) filling a shaft to prepare fracturing construction;

(5) small fracturing tests;

(6) performing fracturing construction according to the design;

the fracturing construction steps are explained by taking a certain section of fracturing as an example:

firstly, completing the perforation bridge plug linkage of the fracturing section according to design;

secondly, soluble plugging balls are thrown on the ground, and the fractured sections are plugged when the balls are placed on bridge plugs;

thirdly, performing first-stage sand fracturing construction;

feeding the temporary plugging agent by a special plugging feeding device, feeding the temporary plugging agent by a constant displacement pump after plugging is finished, observing pressure response after the temporary plugging agent is in place, and finishing feeding the temporary plugging agent after the pressure response meets requirements;

fifthly, performing next-stage sand adding construction;

sixthly, repeating the step four to the step five until the transformation is finished;

the method comprises the following steps of carrying out fracture extension dynamic real-time monitoring and fracture construction dynamic data monitoring by adopting micro-seismic monitoring in a fracturing process, and carrying out real-time fitting by combining the monitored fracture construction dynamic data and the micro-seismic monitoring data to realize inversion of fracture morphology in a temporary plugging diversion fracturing process; when it is monitored that fracture extension which is not beneficial to fracturing is generated in the fracturing section in a certain stage of fracturing process, a temporary plugging adjustment scheme (specifically refer to the description above) is determined in real time, and after temporary plugging adjustment construction is carried out on the fracturing section according to the temporary plugging adjustment scheme, subsequent temporary plugging diversion fracturing construction is carried out;

(7) closing an oil casing wellhead gate in time after fracturing is finished, closing the well for 120min, and controlling open flow to close the crack by using a 10mm oil nozzle (the diffusion pressure time and the open flow process are determined by field technicians);

(8) and (5) handing over the well.

In this embodiment, in the fracturing construction process of the target well, multiple temporary plugging adjustment constructions are performed, and the summary of each temporary plugging adjustment construction scheme is shown in table 1:

TABLE 1

Wherein, the effect pair before and after temporary plugging adjustment construction is performed after a natural crack is pressed open and extends disadvantageously in a certain fracturing process is shown in fig. 5A;

wherein, the effect pair before and after temporary plugging adjustment construction is performed when the two wings of the fracture in the middle stage of fracturing are unbalanced in a certain time, as shown in fig. 5B;

wherein, the effect pairs before and after temporary plugging adjustment construction are carried out when the fracture response points in the middle stage of fracturing are concentrated at a certain time are shown in FIG. 5C;

the effect pair before and after temporary plugging adjustment construction after fracture initial fracture lateral over-expansion occurs at a certain time is shown in fig. 5D.

And 7: after each stage of fracturing of each fracturing section of the target well is completed, analyzing after fracturing respectively, and summarizing relevance and regularity of temporary plugging parameters and implementation effects;

the method comprises the steps of fracturing construction data dynamic fitting, pump-stopping pressure drop test analysis and long-term production data flow field evolution analysis, wherein the post-pressure analysis including fracturing construction data dynamic fitting, pump-stopping pressure drop test analysis and long-term production data flow field evolution analysis is carried out by adopting a comprehensive method of fracturing construction data analysis and test data analysis.

And 8: after the temporary plugging, steering and fracturing of the target well are completed, carrying out productivity fitting;

the method comprises the steps of qualitatively determining the numerical range of key model parameters of a fractured well by adopting a fractured well testing dynamic interpretation method and a numerical simulation dynamic fitting comprehensive method, determining the upper limit and the lower limit of the model parameters according to flow field evolution to be used as parameter value taking domains of a quantitative productivity fitting model, and performing parameter inversion and predicting future yield in the parameter domains by utilizing a constraint optimization method through the numerical simulation dynamic fitting method.

In this embodiment, in the model for numerical fitting when performing capacity fitting, the three-dimensional porosity model is shown in fig. 6A, the three-dimensional permeability model is shown in fig. 6B, the three-dimensional saturation model is shown in fig. 6C, the natural fracture model is shown in fig. 6D, the artificial fracture model is shown in fig. 6E, and the three-dimensional sand body model is shown in fig. 6F and fig. 6G.

In this embodiment, the productivity fitting result is shown in fig. 7.

The above embodiments are merely illustrative of the present invention, and do not limit the scope of the present invention, and the same or similar designs as the present invention fall within the scope of the present invention.

Claims

1. A fine crack control temporary plugging diversion fracturing method, wherein the method comprises the following steps:

wherein the temporary plugging adjustment scheme comprises the delivery times of the temporary plugging agent, and the delivery times of the temporary plugging agent are determined based on the monitored fracture propagation characteristics of the fracture extension which is not beneficial to fracturing:

when the two wings are unbalanced during crack propagation in the middle stage of fracturing, the temporary plugging agent is delivered in a concentrated mode; when the fracture in the initial stage or the middle stage of fracturing is transversely expanded unevenly, the temporary plugging agent is delivered in a grading manner for multiple times; when the fracture at the initial stage of fracturing is transversely over-expanded, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times; when the natural cracks are pressed open in the fracturing process and are not extended, the temporary plugging agent is delivered in a concentrated mode; when the natural cracks are pressed open at the initial stage of fracturing and the natural crack belt is pressed open at the adjacent section of cracks, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times; when the extension net width of the fracture at the initial stage or the middle stage of the fracturing is insufficient, the temporary plugging agent is delivered by multiple grading; when the crack response points in the middle stage of fracturing are concentrated, delivering the temporary plugging agent for multiple times in a grading manner; when the crack response points in the middle stage of fracturing are rarely dispersed, the temporary plugging agent is delivered in a concentrated mode once or in a grading mode for multiple times.

2. The method of claim 1, wherein the temporary plugging agent is delivered in 3-4 stages when the fracture propagation characteristics exhibit an imbalance in fracture initiation or mid-term fracture lateral propagation.

3. The method of claim 1, wherein the temporary plugging agent is delivered in 1-2 passes when the fracture propagation characteristics exhibit fracture initiation fracture lateral overgrowth.

4. The method of claim 1, wherein the temporary plugging agent is delivered in 1-2 deliveries when the fracture propagation characteristics exhibit an early fracture stage fracturing to fracture open the natural fracture and the adjacent stage fracture has fractured the natural fracture band.

5. The method of claim 1, wherein the temporary plugging agent is delivered in 2-4 stages when the fracture propagation characteristics exhibit insufficient initial or intermediate fracture propagation web width.

6. The method of claim 1, wherein,

when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are concentrated, delivering the temporary plugging agent for 2-3 times in a grading way;

and when the crack propagation characteristics show that the response points of the cracks in the middle stage of fracturing are sparsely dispersed, the temporary plugging agent is delivered by grading for 1-2 times.

7. The method of claim 1, wherein the method further comprises:

and when the temporary plugging adjustment scheme is determined, determining the design dosage of each delivery of the temporary plugging agent according to the crack form obtained by inversion.

8. The method according to claim 1 or 7, wherein the temporary plugging adjustment protocol comprises a design dosage for each delivery of the temporary plugging agent, the design dosage for each delivery of the temporary plugging agent being determined based on the following formula:

when the target temporary plugging crack is a horizontal crack,

M_D＝K·π·W_f·[(R+Δd)²-R²]·ρ_D

when the target temporary plugging crack is a vertical crack,

M_D＝π·H·(d·Δd+Δd²)·ρ_D·α·β+π·H·(d·Δd+Δd²)·ρ_D·α

M_Dthe unit kg of the temporary plugging agent is the design dosage for each delivery; h is the seam height of the target temporary plugging crack, and the unit is m; d is the width of the target temporary plugging crack in unit m; delta d is the target thickness of the temporary plugging agent filter cake in m; ρ is a unit of a gradient_DIn order to temporarily block the density of the filter cake, the unit kg/m³(ii) a Beta is a permeability variation coefficient, and the unit is dimensionless; alpha is a crack factor, and the unit is dimensionless.

9. The method according to claim 1, wherein each time the temporary plugging agent is delivered, the temporary plugging agent is delivered according to the designed dosage, and then the following steps are further performed:

10. The method of claim 1, wherein,

the method further comprises the following steps:

a temporary plugging diversion fracturing scheme is formulated before the target well is subjected to temporary plugging diversion fracturing to guide the target well to be subjected to temporary plugging diversion fracturing;

wherein, make the temporary blocking of target well and turn to fracturing scheme and include:

performing geological modeling and fracturing modeling on a target well;

the method further comprises the following steps:

after each stage of fracturing of each fracturing section of the target well is completed, analyzing after fracturing respectively, and summarizing relevance and regularity of temporary plugging parameters and implementation effects;

the method further comprises the following steps:

and performing productivity fitting after the temporary blocking, steering and fracturing of the target well are completed.