CN106869892B - Method for judging temporary plugging and cracking in repeated fracturing well seam - Google Patents

Method for judging temporary plugging and cracking in repeated fracturing well seam Download PDF

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CN106869892B
CN106869892B CN201710155151.8A CN201710155151A CN106869892B CN 106869892 B CN106869892 B CN 106869892B CN 201710155151 A CN201710155151 A CN 201710155151A CN 106869892 B CN106869892 B CN 106869892B
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fracture
temporary plugging
cracking
stress
crack
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CN106869892A (en
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曾凡辉
程小昭
郭建春
陶亮
王小魏
唐波涛
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Southwest Petroleum University
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/25—Methods for stimulating production
    • E21B43/26—Methods for stimulating production by forming crevices or fractures

Abstract

The invention discloses a method for judging temporary plugging and cracking in a repeated fracturing well joint, which comprises the following steps: collecting basic parameters; dividing the hydraulic fracture added with the temporary plugging agent into two hydraulic fractures, and calculating the stress of each point on the fracture surface; establishing a judgment criterion of temporary plugging and cracking turning of the fracture wall surface after the temporary plugging agent is added into the hydraulic fracture through stress analysis of the fracture wall surface; and quantitatively analyzing the influences of different fracture lengths, the net pressure of fluid in the fracture, the temporary plugging agent and the plugging pressure and the plugging length of the temporary plugging agent on the temporary plugging and cracking of the fracture wall surface. The method fully considers the organic combination of the induced stress field generated by hydraulic fracture extension, the induced stress field generated by stratum pore fluid pressure change, the performance parameters of the temporary plugging agent, the plugging length of the temporary plugging agent and other parameters, can effectively predict the fracture initiation position and the orientation of the temporary plugging fracture in the repeated fracturing well joint, and can effectively improve the repeated fracturing temporary plugging steering transformation effect.

Description

Method for judging temporary plugging and cracking in repeated fracturing well seam
Technical Field
The invention relates to a hydraulic fracturing production increase transformation measure of an oil and gas reservoir, in particular to a method for judging temporary plugging and cracking in a repeated fracturing well crack.
Background
The low-permeability oil and gas reservoir generally has the characteristics of low porosity, low permeability, low natural productivity, poor stable production condition and the like, and hydraulic fracturing is a key technology for developing the oil and gas reservoir. The flow conductivity of the hydraulic fracture is gradually reduced until the fracture is invalid after the fracturing well is produced for a long time under the influence of various factors such as engineering geology, construction parameters and the like, and the normal production of the oil-gas well is seriously influenced. For such wells, given that the hydrocarbons controlled by the primary fractures have been substantially produced, new fractures (frac-in-fracture diverting, fig. 1) are typically created by performing a repeated diverting fracturing process to enlarge the communication zone of hydraulic fractures to the hydrocarbons to access hydrocarbon resources outside the old fracture control zone. The key to the success of the process is to judge whether the hydraulic fracture can re-crack a new fracture after the temporary plugging agent is added in the fracturing process.
The existing crack initiation judgment method for the temporary plugging steering crack in the crack mainly comprises the following steps:
(1) song Shao Yun et al (a method for realizing repeated fracturing to create new cracks, patent numbers 200510096443.6, 2005) apply the following criteria to judge that repeated fracturing creates new cracks: when the construction pressure condition meets p in the theoretical criterioninj≥σh+T0,
Figure BDA0001246439270000011
It can be judged that the repeated fracturing process generates a new tensile fracture, wherein pinjTo bottom extension pressure, σH、σhMaximum and small horizontal principal stresses, T, respectively0Rock tensile strength.
(2) Duzon et al (duzon, li jiaqi, ney flood, secondary steering fracturing technology exploration [ J]Xinjiang oil geology, 2013, 34(3):349-IAnd KIIThe fracture criterion is used for researching the problem of the turning crack in the seam, and the theoretical criterion is that when the critical stress intensity factor meets the following conditions:wherein KIcIs a critical stress intensity factor, θ0To the initiation angle, KIIs type I intensity factor, KIIIs type II intensity factor.
(3) The temporary plugging diversion in the repeated fracturing is judged by selecting the condition that the plugging strength of the temporary plugging agent is greater than the difference value between the maximum horizontal main stress and the minimum horizontal main stress of a reconstructed layer position.
The crack initiation judging methods (1) and (3) only consider the influence of the performance parameters (plugging pressure) of the temporary plugging agent on the crack initiation, but neglect the influence of factors such as induced stress generated by hydraulic crack extension and induced stress generated by formation pore fluid pressure change, and cannot judge the initiation direction of a new crack; the method (2) can be used for judging the crack initiation mode of a new crack: opening or shearing, but neglecting the influence caused by the pressure change of the formation pore fluid, the performance parameters of the temporary plugging agent and the like.
The method for judging the initiation of the temporary plugging steering fracture in the repeated fracturing well fracture cannot analyze the influence of the position of the temporary plugging agent on the initiation of a new fracture, and does not organically combine hydraulic fracture induced stress, induced stress generated by the pressure drop of formation pore fluid due to production and plugging capacity parameters of the temporary plugging agent.
Disclosure of Invention
The invention aims to provide a method for judging temporary plugging and cracking in a repeated fracturing well joint, which can improve the reconstruction effect of the repeated fracturing temporary plugging steering and aims to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme:
a method for judging temporary plugging and cracking in a repeated fracturing well crack comprises the following specific steps:
1) collecting basic parameters of a reservoir, including formation parameters, hydraulic fracture parameters, construction parameters and temporary plugging agent performance parameters;
2) dividing the hydraulic fracture added with the temporary plugging agent into two hydraulic fractures, and calculating the stress of each point on the fracture surface;
3) establishing a judgment criterion of temporary plugging and cracking turning of the fracture wall surface after the temporary plugging agent is added into the hydraulic fracture through stress analysis of the fracture wall surface;
4) and quantitatively analyzing the influences of different crack lengths, the net pressure of the fluid in the crack, the blocking pressure of the temporary blocking agent and the blocking length of the temporary blocking agent on the temporary blocking and cracking of the wall surface of the crack.
As a further scheme of the invention: the basic parameters in step 1) specifically include: maximum and minimum horizontal principal stress of the formation, original formation pressure and current formation pressure, poisson's ratio and tensile strength of rock, hydraulic fracture length, net pressure of fluid in the fracture, plugging length of temporary plugging agent and plugging pressure parameters.
As a further scheme of the invention: the two hydraulic fractures in the step 2) are respectively HF1And HF2Each length of l1And l2And the tip of each hydraulic fracture is O1And O2(ii) a The length of the original hydraulic fracture half wing is LfTemporarily for a whileThe plugging length of the plugging agent in the crack is d.
As a further scheme of the invention: and in the step 3), stress on the fracture wall surface is the superposition of induced stress generated by hydraulic fracture extension and induced stress generated by formation pore fluid pressure change and in-situ stress.
As a further scheme of the invention: the induced stress generated by the hydraulic fracture propagation is calculated as follows:
Figure BDA0001246439270000031
in the formula: sigmaxx1、σyy1、τxy1Respectively the induced normal stress and the induced shear stress components, MPa, generated in the x and y directions by hydraulic fracture extension;
Figure BDA0001246439270000032
are each O1And O2Stress intensity factor of end rock, its value is
Figure BDA0001246439270000033
Andwherein p isnet1、pnet2Respectively, is a crack HF1And HF2The net internal pressure is set to a value that,
Figure BDA0001246439270000035
Figure BDA0001246439270000036
respectively point on the fracture face to the hydraulic fracture tip O1And O2The angle between the connecting line of (d) and the direction of the maximum horizontal principal stress, rad;
Figure BDA0001246439270000037
Figure BDA0001246439270000038
respectively point-to-hydraulic fracture on fracture faceSuture tip O1And O2M, m.
As a further scheme of the invention: the induced stress resulting from the formation fluid pressure change is calculated as follows:
in the formula: sigmaxx2，σyy2Respectively are induced stress components, MPa, generated in the x and y directions by the pressure change of formation pore fluid; nu is the Poisson's ratio of reservoir rock and has no dimension; alpha is a Biot porous elastic coefficient and has no dimension; p is a radical ofpCurrent formation pressure, MPa; p is a radical ofeOriginal formation pressure, MPa.
As a further scheme of the invention: the superposition of the induced stress and the in situ stress is calculated as follows:
Figure BDA0001246439270000041
substituting the formulas (1) and (2) into the formula (3) to obtain the stress distribution of any point of the crack wall surface:
Figure BDA0001246439270000042
in the formula: sigmax，σy，τxyRespectively, the normal and shear stress components in x and y coordinates, MPa.
As a further scheme of the invention: the judgment criterion of the fracture wall surface temporary plugging and cracking turning after adding the temporary plugging agent into the hydraulic fracture in the step 3) is as follows:
maximum principal stress sigma at any point of hydraulic fracture wall surface1Comprises the following steps:
Figure BDA0001246439270000043
applying the maximum tensile stress criterion, i.e. the maximum principal stress sigma, to the new fracture initiation criterion of the hydraulic fracture wall1Greater than tensile strength T of rock0And then, cracking the rock on the wall surface of the crack:
σ1≥T0 (6)
the crack initiation angle γ is:
wherein, the gamma value is positive, which indicates that the rock on the wall surface of the crack breaks upwards; the gamma value is negative, indicating that the rock on the fracture wall is broken downwards.
As a still further scheme of the invention: the step 4) is specifically to quantitatively analyze the HF of the fracture by combining basic parameters including formation parameters, hydraulic fracture parameters, construction parameters and temporary plugging agent performance parameters1Length l of1Crack HF1Net pressure p of internal fluidnet1The plugging pressure delta p of the temporary plugging agent and the plugging length d of the temporary plugging agent are used for cracking HF1And crack HF2The effect of wall cracking.
Compared with the prior art, the invention has the beneficial effects that:
the method fully considers the organic combination of the induced stress field generated by hydraulic fracture extension, the induced stress field generated by stratum pore fluid pressure change, the performance parameters of the temporary plugging agent, the plugging length of the temporary plugging agent and other parameters, can effectively predict the fracture initiation position and the orientation of the temporary plugging fracture in the repeated fracturing well joint, and can effectively improve the repeated fracturing temporary plugging steering transformation effect.
Drawings
FIG. 1 is a schematic view of temporary plugging turning in a repeat fracturing.
FIG. 2 is a schematic diagram of a physical model of temporary plugging in a repeated fracturing fracture.
FIG. 3 shows a crack HF in an embodiment of the invention1Length l of1Change to tip O1And O2The effect of cracking is shown schematically.
FIG. 4 shows an embodiment of the present inventionMiddle crack HF1Internal net pressure pnet1Change to tip O1And O2The effect of cracking is shown schematically.
FIG. 5 shows the variation of plugging pressure Δ p versus tip O of the temporary plugging agent in the embodiment of the present invention1And O2The effect of cracking is shown schematically.
FIG. 6 shows the variation of plugging length d versus tip O of the temporary plugging agent in the embodiment of the present invention1And O2The effect of cracking is shown schematically.
Detailed Description
The technical solution of the present patent will be described in further detail with reference to the following embodiments.
A method for judging temporary plugging and cracking in a repeated fracturing well crack comprises the following specific steps:
1) collecting basic parameters of a reservoir, including formation parameters, hydraulic fracture parameters, construction parameters and temporary plugging agent performance parameters;
2) dividing the hydraulic fracture added with the temporary plugging agent into two hydraulic fractures, and calculating the stress of each point on the fracture surface;
3) establishing a judgment criterion of temporary plugging and cracking turning of the fracture wall surface after the temporary plugging agent is added into the hydraulic fracture through stress analysis of the fracture wall surface;
4) and quantitatively analyzing the influences of different crack lengths, the net pressure of the fluid in the crack, the blocking pressure of the temporary blocking agent and the blocking length of the temporary blocking agent on the temporary blocking and cracking of the wall surface of the crack.
The basic parameters in step 1) specifically include: maximum and minimum horizontal principal stress of the formation, original formation pressure and current formation pressure, poisson's ratio and tensile strength of rock, hydraulic fracture length, net pressure of fluid in the fracture, plugging length of temporary plugging agent and plugging pressure parameters.
The two hydraulic fractures in the step 2) are respectively HF1And HF2Each length of l1And l2And the tip of each hydraulic fracture is O1And O2(ii) a The length of the original hydraulic fracture half wing is LfThe plugging length of the temporary plugging agent in the crack is d.
And in the step 3), stress on the fracture wall surface is the superposition of induced stress generated by hydraulic fracture extension and induced stress generated by formation pore fluid pressure change and in-situ stress, and the tension is positive and the pressure is negative.
The induced stress generated by the hydraulic fracture propagation is calculated as follows:
Figure BDA0001246439270000061
Figure BDA0001246439270000062
Figure BDA0001246439270000063
in the formula: sigmaxx1、σyy1、τxy1Respectively the induced normal stress and the induced shear stress components, MPa, generated in the x and y directions by hydraulic fracture extension;
Figure BDA0001246439270000064
are each O1And O2Stress intensity factor of the tip rock, its value isAnd
Figure BDA0001246439270000066
wherein p isnet1、pnet2Respectively, is a crack HF1And HF2The net internal pressure is set to a value that,
Figure BDA0001246439270000067
Figure BDA0001246439270000068
respectively point on the fracture face to the hydraulic fracture tip O1And O2The angle between the connecting line of (d) and the direction of the maximum horizontal principal stress, rad;
Figure BDA0001246439270000069
respectively point on the fracture face to the hydraulic fracture tip O1And O2M;
the induced stress generated by the formation pore fluid pressure change is calculated as follows:
Figure BDA00012464392700000610
Figure BDA00012464392700000611
in the formula: sigmaxx2，σyy2Respectively are induced stress components, MPa, generated in the x and y directions by the pressure change of formation pore fluid; nu is the Poisson's ratio of reservoir rock and has no dimension; alpha is a Biot porous elastic coefficient and has no dimension; p is a radical ofpCurrent formation pressure, MPa; p is a radical ofeOriginal formation pressure, MPa;
the superposition of the induced stress and the in situ stress is calculated as follows:
σx＝σH+σxx1+σxx2
σy＝σh+σyy1+σyy2
τxy＝τxy1 (3)
substituting the formulas (1) and (2) into the formula (3) to obtain the stress distribution of any point of the crack wall surface:
Figure BDA0001246439270000071
in the formula: sigmax，σy，τxyRespectively are the normal stress and the shear stress component under x and y coordinates, MPa;
the judgment criterion of the fracture wall surface temporary plugging and cracking turning after adding the temporary plugging agent into the hydraulic fracture in the step 3) is as follows:
maximum principal stress sigma at any point of hydraulic fracture wall surface1Is (stipulated: pull "+", press "-"):
applying the maximum tensile stress criterion, i.e. the maximum principal stress sigma, to the new fracture initiation criterion of the hydraulic fracture wall1Greater than tensile strength T of rock0And then, cracking the rock on the wall surface of the crack:
σ1≥T0 (6)
the crack initiation angle γ is:
Figure BDA0001246439270000073
wherein, the gamma value is positive, which indicates that the rock on the wall surface of the crack breaks upwards; the gamma value is negative, indicating that the rock on the fracture wall is broken downwards.
The step 4) is specifically to quantitatively analyze the HF of the fracture by combining basic parameters including formation parameters, hydraulic fracture parameters, construction parameters, temporary plugging agent performance parameters and the like1Length l of1Crack HF1Net pressure p of internal fluidnet1The plugging pressure delta p of the temporary plugging agent and the plugging length d of the temporary plugging agent are used for cracking HF1And crack HF2The effect of wall cracking.
Example (b):
referring to fig. 1-6, a method for determining temporary plugging and cracking in a fractured well fracture by repeated fracturing specifically includes the following steps:
the basic parameters are as follows: maximum horizontal principal stress σHIs 47MPa, minimum level principal stress sigmah36MPa, original formation pressure pe24.3MPa, current formation pressure pp13MPa, Poisson's ratio v of rock of 0.31, and tensile strength T of rock03MPa, Biot coefficient 0.9, original hydraulic fracture half length Lf340m, crack HF1Length 250m, crack HF1The internal net pressure is 30MPa, the plugging length d of the temporary plugging agent in the crack is 30m, and the plugging pressure delta p of the temporary plugging agent is 15 MPa.
(1) Crack HF1Length l1Influence on temporary plugging cracking
FIG. 3 characterizes fracture HF1Length l of1Change to tip O1And O2The effect of the crack initiation can be seen in fig. 3: when the crack HF is determined by other calculation parameters1Length l of1<20m, crack only HF2O of (A) to (B)2Cracking the tip; when 20m is less than or equal to l1Crack HF less than or equal to 300m1O of (A) to (B)1Tip and crack HF2O of (A) to (B)2The tips all crack; when l is1>300m, only crack HF1O of (A) to (B)1The tip cracks.
(2) Crack HF1Internal net pressure pnet1Influence on temporary plugging cracking
FIG. 4 characterizes fracture HF1Internal net pressure pnet1Change to tip O1And O2The effect of the crack initiation can be seen in fig. 4: when the crack HF is determined by other calculation parameters1Internal net pressure pnet1<At 25MPa, only crack HF1O of (A) to (B)1Cracking the tip; when p isnet1Crack HF at not less than 25MPa1O of (A) to (B)1Tip and crack HF2O of (A) to (B)2The tips all cracked.
(3) Influence of plugging pressure delta p of temporary plugging agent on temporary plugging cracking
FIG. 5 is a graph depicting the change in plugging pressure Δ p versus tip O for the transient plugging agent1And O2The effect of cracking can be seen from the figure: when other calculation parameters are fixed, when the plugging pressure delta p of the temporary plugging agent is less than or equal to 20MPa, the crack HF is1O of (A) to (B)1Tip and crack HF2O of (A) to (B)2The tips all crack; when Δ p>At 20MPa, only crack HF1O of (A) to (B)1The tip cracks.
(4) Influence of plugging length d of temporary plugging agent on temporary plugging cracking
FIG. 6 is a graph depicting the variation of occlusion length d versus tip O for a temporary occlusion agent1And O2The effect of cracking can be seen from the figure: when other calculation parameters are fixed, when the plugging length d of the temporary plugging agent is less than or equal to 60m, the crack HF is1O of (A) to (B)1Tip and crack HF2O of (A) to (B)2The tips all crack; when d is>At 60m, only crack HF1O of (A) to (B)1The tip cracks.
The method for judging the temporary plugging and cracking in the repeated fracturing well can effectively judge whether the wall surface of the fracture can be cracked again after the temporary plugging agent is added into the hydraulic fracture and determine the cracking direction, so that the steering transformation effect of the repeated fracturing temporary plugging is improved. According to basic parameters of stratum parameters, hydraulic fracture parameters, construction parameters, temporary plugging agent performance parameters and the like of a reservoir, dividing the hydraulic fracture into two hydraulic fractures after the temporary plugging agent is added, and thus establishing a judgment model of temporary plugging and cracking steering of the fracture wall surface after the temporary plugging agent is added into the hydraulic fracture; and quantitatively analyzing the influences of different crack lengths, the net pressure of fluid in the crack, the blocking pressure of the temporary plugging agent (pressure drop loss caused by the fluid breaking through the temporary plugging agent), the blocking length of the temporary plugging agent and the like on the temporary plugging and cracking of the wall surface of the crack.
The method fully considers the organic combination of the induced stress field generated by hydraulic fracture extension, the induced stress field generated by stratum pore fluid pressure change, the performance parameters of the temporary plugging agent, the plugging length of the temporary plugging agent and other parameters, can effectively predict the fracture initiation position and direction of the repeated fracturing well fracture, and can effectively improve the repeated fracturing temporary plugging steering transformation effect.
Although the preferred embodiments of the present patent have been described in detail, the present patent is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present patent within the knowledge of those skilled in the art.

Claims (9)

1. A method for judging temporary plugging and cracking in a repeated fracturing well joint is characterized by comprising the following specific steps:
1) collecting basic parameters of a reservoir, including formation parameters, hydraulic fracture parameters, construction parameters and temporary plugging agent performance parameters;
2) dividing the hydraulic fracture added with the temporary plugging agent into two hydraulic fractures, and calculating the stress of each point on the fracture wall surface;
3) establishing a judgment criterion of temporary plugging and cracking turning of the fracture wall surface after the temporary plugging agent is added into the hydraulic fracture through stress analysis of the fracture wall surface;
4) and quantitatively analyzing the influences of different crack lengths, the net pressure of the fluid in the crack, the blocking pressure of the temporary blocking agent and the blocking length of the temporary blocking agent on the temporary blocking and cracking of the wall surface of the crack.
2. The method for judging the temporary plugging and cracking in the repeated fracturing well joint as claimed in claim 1, wherein the basic parameters in the step 1) specifically comprise: maximum and minimum horizontal principal stress of the formation, original formation pressure and current formation pressure, poisson's ratio and tensile strength of rock, hydraulic fracture length, net pressure of fluid in the fracture, plugging length of temporary plugging agent and plugging pressure parameters.
3. The method for judging the temporary plugging and cracking in the repeated fracturing well gap according to claim 1, wherein the two hydraulic gaps in the step 2) are HF respectively1And HF2Each length of l1And l2And the tip of each hydraulic fracture is O1And O2(ii) a The length of the original hydraulic fracture half wing is LfThe plugging length of the temporary plugging agent in the crack is d.
4. The method for determining the temporary blocking and cracking in the repeated fracturing well gap according to claim 3, wherein the stress on the wall surface of the gap in the step 3) is the superposition of an induced stress generated by the extension of a hydraulic gap and an induced stress generated by the pressure change of a formation pore fluid and an in-situ stress.
5. The method for judging the temporary plugging and cracking in the repeated fracturing well gap according to claim 4, wherein the induced stress generated by the extension of the hydraulic fracture is calculated as follows:
Figure FDA0002116063480000011
in the formula: sigmaxx1、σyy1、τxy1Induced normal stress and inducement in x and y directions for hydraulic fracture propagation, respectivelyGuiding shear stress component, MPa;
Figure FDA0002116063480000021
are each O1And O2Stress intensity factor of the tip rock, its value is
Figure FDA0002116063480000022
And
Figure FDA0002116063480000023
wherein p isnet1、pnet2Respectively, is a crack HF1And HF2The net internal pressure is set to a value that,
Figure FDA0002116063480000024
Figure FDA0002116063480000025
respectively point on the fracture wall surface to the hydraulic fracture tip O1And O2The angle between the connecting line of (d) and the direction of the maximum horizontal principal stress, rad;
Figure FDA0002116063480000026
Figure FDA0002116063480000027
respectively point on the fracture wall surface to the hydraulic fracture tip O1And O2M, m.
6. The method for judging the temporary plugging and cracking in the repeated fracturing well gap according to claim 5, wherein the induced stress generated by the change of the formation pore fluid pressure is calculated as follows:
Figure FDA0002116063480000028
in the formula: sigmaxx2，σyy2Induced stress in x and y directions for formation pore fluid pressure changes, respectivelyComponent, MPa; nu is the Poisson's ratio of reservoir rock and has no dimension; alpha is a Biot porous elastic coefficient and has no dimension; p is a radical ofpCurrent formation pressure, MPa; p is a radical ofeOriginal formation pressure, MPa.
7. The method for determining the temporary plugging and cracking in the repeated fracturing well gap according to claim 6, wherein the superposition of the induced stress generated by the hydraulic fracture extension and the induced stress generated by the pressure change of the formation pore fluid and the in-situ stress is calculated as follows:
Figure FDA0002116063480000029
substituting the formulas (1) and (2) into the formula (3) to obtain the stress distribution of any point of the crack wall surface:
Figure FDA00021160634800000210
in the formula: sigmax，σy，τxyRespectively are the normal stress and the shear stress component under x and y coordinates, MPa; sigmaHIs the maximum horizontal principal stress, σhIs the minimum level principal stress.
8. The method for judging the temporary plugging and cracking in the repeated fracturing well joint according to claim 7, wherein the judgment criteria of the temporary plugging and cracking turning of the fracture wall surface after the temporary plugging agent is added into the hydraulic fracture in the step 3) are as follows:
maximum principal stress sigma at any point of hydraulic fracture wall surface1Comprises the following steps:
Figure FDA0002116063480000031
applying the maximum tensile stress criterion, i.e. the maximum principal stress sigma, to the new fracture initiation criterion of the hydraulic fracture wall1Greater than tensile strength T of rock0And then, cracking the rock on the wall surface of the crack:
σ1≥T0 (6)
the crack initiation angle γ is:
Figure FDA0002116063480000032
wherein, the gamma value is positive, which indicates that the rock on the wall surface of the crack breaks upwards; the gamma value is negative, indicating that the rock on the fracture wall is broken downwards.
9. The method for judging the temporary plugging and cracking in the repeated fracturing well joint as claimed in claim 1, wherein the step 4) is specifically to quantitatively analyze the HF of the fracture by combining basic parameters including formation parameters, hydraulic fracture parameters, construction parameters and performance parameters of temporary plugging agents1Length l of1Crack HF1Net pressure p of internal fluidnet1The plugging pressure delta p of the temporary plugging agent and the plugging length d of the temporary plugging agent are used for cracking HF1And crack HF2The effect of wall cracking.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4718490A (en) * 1986-12-24 1988-01-12 Mobil Oil Corporation Creation of multiple sequential hydraulic fractures via hydraulic fracturing combined with controlled pulse fracturing
CN103306660A (en) * 2012-03-13 2013-09-18 中国石油化工股份有限公司 Shale gas reservoir hydraulic fracturing production increasing method
CN105003240A (en) * 2015-07-15 2015-10-28 西南石油大学 Hydrofracture design parameter optimization method based on fine classification of reservoir
CN105927197A (en) * 2016-04-27 2016-09-07 中国石油天然气股份有限公司 Method for increasing production by old well temporary plugging volume fracturing repeated reconstruction in low permeability sandstone reservoir

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4718490A (en) * 1986-12-24 1988-01-12 Mobil Oil Corporation Creation of multiple sequential hydraulic fractures via hydraulic fracturing combined with controlled pulse fracturing
CN103306660A (en) * 2012-03-13 2013-09-18 中国石油化工股份有限公司 Shale gas reservoir hydraulic fracturing production increasing method
CN105003240A (en) * 2015-07-15 2015-10-28 西南石油大学 Hydrofracture design parameter optimization method based on fine classification of reservoir
CN105927197A (en) * 2016-04-27 2016-09-07 中国石油天然气股份有限公司 Method for increasing production by old well temporary plugging volume fracturing repeated reconstruction in low permeability sandstone reservoir

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