A method for calculating the heating transformation range and permeability of shale oil reservoirs

Abstract

The invention discloses a method for calculating the heating transformation range and permeability of a shale oil reservoir, and belongs to the technical field of petroleum exploitation and development research; the invention first constructs a shale oil reservoir horizontal well heating model to heat and transform the shale oil reservoir, and then constructs an infinite and closed-boundary shale oil reservoir heating development physical model based on the production history data of the selected shale oil reservoir; based on the physical model, a corresponding mathematical model is further constructed, and the bottom hole pressure solution of the horizontal well is calculated by using the mathematical model, and the bottom hole pressure solution of the horizontal well is compared with the production history data to determine the heating transformation range and the permeability of the transformation area; the invention accurately and reliably calculates the transformation range and permeability after heating by studying and analyzing the heating and utilization law of shale oil formations, thereby providing theoretical guidance for the prediction of the heating transformation range and permeability in the heating development process of shale oil reservoirs.

Description

Technical Field

[0001] The invention relates to the technical field of petroleum exploitation and development research, and in particular to a method for calculating the heating transformation range and permeability of a shale oil reservoir. Background Art

[0002] my country has abundant shale oil and gas reserves, but shale oil and gas extraction technology started late and still has many shortcomings, making it impossible to fully and efficiently develop shale oil and gas reservoirs. Since most shale oil reservoirs have the characteristics of low porosity and low permeability, they are difficult to exploit with low maturity, and the development of high-maturity shale oil reservoirs is difficult. At present, the development of medium- and low-maturity shale oil reservoirs mainly uses hydraulic fracturing and in-situ heating and modification to enhance the fluidity and permeability of shale oil and reservoirs to improve the recovery rate of shale oil and gas. Among them, in-situ heating modification technology is considered to be an effective technology for the exploitation of medium- and low-maturity shale oil, with broad development prospects and high application value. Under the coupling of physical and chemical fields, the pore structure of shale reservoirs further evolves, and the fluidity and permeability of shale reservoirs are further improved. Formulating a suitable heating scheme is an important factor in balancing the economy and rationality of in-situ heating modification technology. Therefore, it is of practical significance to study the impact of shale oil reservoir heating on its transformation range and permeability. In view of this, the present invention proposes a method for calculating the heating transformation range and permeability of a shale oil reservoir. Summary of the invention

[0003] The purpose of the present invention is to provide a method for calculating the heating transformation range and permeability of shale oil reservoirs to solve the problems raised in the background technology. By studying and analyzing the heating and utilization laws of shale oil formations, the transformation range and permeability after heating are accurately and reliably calculated, so as to provide theoretical guidance for the prediction of the heating transformation range and permeability in the heating development process of shale oil reservoirs.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for calculating the heating transformation range and permeability of a shale oil reservoir comprises the following steps:

[0006] S1. Select appropriate medium-low maturity shale oil reservoirs, design heating transformation methods in the heating development process of shale oil reservoirs, and construct a horizontal well heating model for shale oil reservoirs;

[0007] S2. Establishing a shale oil reservoir heating development and transformation scope and a permeability physical model based on the shale oil reservoir selected in S1;

[0008] S3, based on the shale oil reservoir heating development and transformation range and permeability physical model constructed in S2, a shale oil reservoir heating development and transformation range and permeability mathematical model is established to calculate the bottom hole pressure solution of the horizontal well;

[0009] S4. Compare the pressure solution calculated in S3 with the actual pressure after heating to determine the heating transformation range and the permeability of the transformation area.

[0010] Preferably, the heating transformation method in the shale oil reservoir heating development process described in S1 includes the following contents:

[0011] S1.1. Select a suitable medium-low maturity shale oil reservoir and drill a horizontal well into the shale oil reservoir;

[0012] S1.2, install several electromagnetic heating devices at equal intervals on the wellbore of the horizontal well to heat the shale oil reservoir, and lead them out of the wellhead through cables;

[0013] S1.3. Power the wellhead cable and heat the shale oil reservoir to 400-500°C through an electromagnetic heating device to promote rapid maturation of organic matter in the shale oil reservoir, promote fracturing and reduce viscosity.

[0014] Preferably, the shale oil reservoir heating development and transformation scope and permeability physical model in S2 includes an infinite shale oil reservoir heating development and transformation scope and permeability physical model and a closed boundary shale oil reservoir heating development and transformation scope and permeability physical model; wherein the assumptions of the infinite shale oil reservoir heating development and transformation scope and permeability physical model include:

[0015] (1) Horizontal wells are considered as linear sources and produce at a fixed rate, with infinite horizontal diversion;

[0016] (2) The fluid flow in shale oil reservoirs belongs to late pseudo-planar radial flow;

[0017] (3) Both the inner and outer zones of the shale oil reservoir are fracture-matrix dual media;

[0018] (4) During the heating transformation process, the fluid flows in a single phase and satisfies Darcy's law;

[0019] (5) Ignore the effects of gravity and capillary forces;

[0020] (6) Consider the skin effect S and the wellbore reservoir effect C;

[0021] (7) The horizontal and vertical permeabilities of the reservoir are different.

[0022] Preferably, S3 specifically includes the following contents:

[0023] S3.1. Establishing a shale oil reservoir heating development and transformation scope and a permeability mathematical model based on the physical model;

[0024] S3.2, Laplace transformation is performed on the shale oil reservoir heating development and transformation range and permeability mathematical model by dimensionless variables, and a semi-analytical method is used to solve the shale oil reservoir heating development and transformation range and permeability mathematical model obtained in S3.1 to obtain the bottom hole pressure solution of the horizontal well in the Laplace domain;

[0025] S3.3. The Stehfest numerical inversion method is used for the bottom hole pressure solution of the horizontal well in the Laplace domain obtained in S3.2 to obtain the pressure solution of the shale oil reservoir heating development and transformation range and the permeability mathematical model under two boundary conditions in the real domain.

[0026] Preferably, the shale oil reservoir heating development and transformation scope and permeability mathematical model specifically include the following contents:

[0027] (1) Control equation of the inner zone crack system:

[0028]

[0029] (2) Control equation of the inner zone matrix system:

[0030]

[0031] (3) Control equation of the external zone crack system:

[0032]

[0033] (4) Control equation of the outer zone matrix system:

[0034]

[0035] (5) Boundary conditions of the transformation area:

[0036]

[0037] (6) Infinite boundary conditions in the outer region:

[0038] ΔP c2 (R→∞,t)=0

[0039] (7) External closed boundary conditions:

[0040]

[0041] (8) Continuous boundary conditions between the transformation area and the external area:

[0042] ΔP c1 (R 1 ,t)=ΔP c1 (R 1 ,t)

[0043]

[0044] (9) Initial conditions of the transformation area and the external area:

[0045] ΔP ci | t＝0 =0 (i=1,2)

[0046] ΔP mi | t＝0 =0 (i=1,2)

[0047] Wherein, subscripts 1 and 2 represent the reformed area and the unreformed area, respectively; subscripts c and m represent the fracture system and the matrix system, respectively; P ci represents the fracture system pressure in zone i; P mi represents the matrix system pressure in zone i; P 0 Indicates the original formation pressure; ΔP ci =P 0 -P ci ; ΔP mi =P 0 -P mi ; Q is the oil well production; t is the production time; h is the reservoir thickness; μ i is the viscosity of the fluid in zone i; φ ci is the porosity of the fracture system in zone i; φ mi is the porosity of the matrix system in zone i; K chi is the horizontal permeability of the fracture system in zone i; K cvi is the vertical permeability of the fracture system in zone i; K mhi is the horizontal permeability of the matrix system in zone i; K mvi is the vertical permeability of the matrix system in zone i; C cti is the comprehensive compression coefficient of the crack system in zone i; C mti is the comprehensive compressibility coefficient of the matrix system in zone i; B is the fluid volume coefficient; Z w is the distance from the horizontal well to the reservoir bottom; ε is the vertical length; β mi is the reservoir matrix system shape factor of the i-th zone; C is the wellbore storage coefficient; R e Is the outer border radius.

[0048] Preferably, dimensionless variable technology is used to simplify the mathematical model and define dimensionless variables:

[0049] (1) Dimensionless pressure:

[0050]

[0051] (2) Dimensionless production time:

[0052]

[0053] (3) Dimensionless wellbore storage coefficient:

[0054]

[0055] (4) Dimensionless radial and horizontal distances:

[0056]

[0057] (5) Dimensionless vertical distance:

[0058]

[0059] (6) Dimensionless horizontal well length:

[0060]

[0061] (7) Pressure conductivity ratio:

[0062]

[0063] (8) Mobility ratio:

[0064]

[0065] (9) Crossflow coefficient:

[0066]

[0067] (10) Fracture system storage ratio:

[0068]

[0069] (11) Matrix system storage ratio:

[0070]

[0071] Preferably, the Laplace transform is used to solve the range of heating development and transformation of shale oil reservoirs and the mathematical model of permeability under the infinite boundary, which specifically includes the following contents:

[0072] The dimensionless bottom hole pressure solution of a horizontal well under infinite boundary is:

[0073]

[0074] Where:

[0075]

[0076] e n1 =f 1 (e)e+(nπL D1 ) 2

[0077]

[0078] Where: e is the Laplace variable; I 0 (x),I 1 (x) are the first-order zero-order and first-order Bessel functions respectively; K 0 (x),K 1 (x) are the zero-order and first-order Bessel functions of the second kind, respectively.

[0079] Preferably, the Laplace transform is used to solve the heating development and transformation range and permeability mathematical model of the shale oil reservoir under the closed boundary, which specifically includes the following contents:

[0080] The dimensionless bottom hole pressure solution of a horizontal well under a closed boundary is:

[0081]

[0082] Where:

[0083]

[0084] Preferably, the S3.3 specifically includes the following contents:

[0085] The Laplace inverse transformation is performed on the pressure solution of the shale oil reservoir heating development and transformation scope and the permeability prediction model in the Laplace domain:

[0086]

[0087] Given u and t, calculate P wD The value is obtained, and the scope of shale oil reservoir heating development and transformation and the pressure solution of the permeability prediction model in the real domain are obtained.

[0088] Preferably, the S4 specifically includes the following contents:

[0089] S4.1. Using the pressure solution of the horizontal well in the real domain and the actual pressure recovery data, a double logarithmic curve of pressure recovery is drawn in a double logarithmic coordinate system with pressure and pressure derivative as the ordinate and time as the abscissa;

[0090] S4.2. Determine the R under two boundary conditions by fitting the predicted double logarithmic curve with the actual double logarithmic curve. D1 , R D1 The heating transformation range is determined, and the permeability of the transformation area after heating is further determined.

[0091] Compared with the prior art, the present invention provides a method for calculating the heating transformation range and permeability of shale oil reservoirs, which has the following beneficial effects:

[0092] The present invention designs a method for calculating the heating transformation range and permeability of a shale oil reservoir. First, a horizontal well heating model of a shale oil reservoir is constructed to heat and transform the shale oil reservoir. Then, a physical model of the heating development and transformation range and permeability of a shale oil reservoir with an infinite size and a closed boundary is constructed according to the production history data of the selected shale oil reservoir. A corresponding mathematical model is further constructed based on the physical model, and the bottom hole pressure solution of the horizontal well is calculated by using the mathematical model. The bottom hole pressure solution of the horizontal well obtained is compared with the actual pressure after heating to determine the heating transformation range and the permeability of the transformation area. The present invention accurately and reliably calculates the transformation range and permeability after heating by studying and analyzing the heating and utilization law of shale oil formations, thereby providing theoretical guidance for the prediction of the heating transformation range and permeability in the heating development process of shale oil reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] Figure 1 Schematic diagram of the shale oil reservoir horizontal well heating model mentioned in Example 1 of the present invention

[0094] Figure 2 A schematic diagram of the scope of the rock oil reservoir heating development and transformation and the permeability physical model mentioned in Example 1 of the present invention;

[0095] Figure 3 It is a schematic diagram of the pressure and inverse pressure curve of a horizontal well under the infinite boundary mentioned in Example 1 of the present invention;

[0096] Figure 4 It is a schematic diagram of the pressure and pressure inverse curve of the horizontal well under the closed boundary mentioned in Example 1 of the present invention. DETAILED DESCRIPTION

[0097] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0098] Embodiment 1:

[0099] The present invention proposes a method for calculating the heating transformation range and permeability of a shale oil reservoir, which includes the following contents:

[0100] Step 1

[0101] See also Figure 1, select a suitable medium-to-low maturity shale oil reservoir, and drill a horizontal well into the shale oil reservoir; then install several electromagnetic heating devices at equal intervals on the wellbore of the horizontal well to heat the shale oil reservoir, and lead them out of the wellhead through cables; energize the wellhead cable, and heat the shale oil reservoir to about 450°C through the electromagnetic heating device, so as to promote the rapid maturation of organic matter in the shale oil reservoir, promote cracking and reduce viscosity, and achieve the purpose of facilitating mining.

[0102] Step 2

[0103] According to the production history data of the shale oil reservoir selected in step 1, a shale oil reservoir heating development and transformation scope and permeability physical model is established; the physical model includes a shale oil reservoir heating development and transformation scope and permeability physical model under an infinite boundary and a shale oil reservoir heating development and transformation scope and permeability physical model under a closed boundary, wherein the production history data such as geological parameters and fluid properties corresponding to the shale oil reservoir heating development and transformation scope and permeability physical model under an infinite boundary are shown in Table 1:

[0104] Table 1 Input parameters under infinite boundary

[0105]

[0106] The production history data of the heating development and transformation scope of shale oil reservoirs under closed boundaries and the geological parameters and fluid properties corresponding to the permeability physical model are shown in Table 2:

[0107] Table 2 Input parameters under closed boundary

[0108]

[0109] The physical models under the two boundary conditions are as follows: Figure 2 As shown in the figure, the assumptions of the infinite shale oil reservoir heating development and transformation scope and the permeability physical model include:

[0110] (1) Horizontal wells are considered as linear sources and produce at a fixed rate, with infinite horizontal diversion;

[0111] (2) The fluid flow in shale oil reservoirs belongs to late pseudo-planar radial flow;

[0112] (3) Both the inner and outer zones of the shale oil reservoir are fracture-matrix dual media;

[0113] (4) During the heating transformation process, the fluid flows in a single phase and satisfies Darcy's law;

[0114] (5) Ignore the effects of gravity and capillary forces;

[0115] (6) Consider the skin effect S and the wellbore reservoir effect C;

[0116] (7) The horizontal and vertical permeabilities of the reservoir are different.

[0117] The assumptions of the closed boundary physics model are the same as those of the infinite size physics model except that the boundary is a closed boundary.

[0118] Step 3

[0119] Based on the physical model, the scope of shale oil reservoir heating development and transformation and the mathematical model of permeability are established, which specifically includes the following contents:

[0120] 1) Control equation of the inner zone crack system:

[0121]

[0122] (2) Control equation of the inner zone matrix system:

[0123]

[0124] (3) Control equation of the external zone crack system:

[0125]

[0126] (4) Control equation of the outer zone matrix system:

[0127]

[0128] (5) Boundary conditions of the transformation area:

[0129]

[0130]

[0131] (6) Infinite boundary conditions in the outer region:

[0132] ΔP c2 (R→∞,t)=0

[0133] (7) External closed boundary conditions:

[0134]

[0135] (8) Continuous boundary conditions between the transformation area and the external area:

[0136] ΔP c1 (R 1 ,t)=ΔP c1 (R 1 ,t)

[0137]

[0138] (9) Initial conditions of the transformation area and the external area:

[0139] ΔP ci | t＝0 =0 (i=1,2)

[0140] ΔP mi | t＝0 =0 (i=1,2)

[0141] Wherein, subscripts 1 and 2 represent the reformed area and the unreformed area, respectively; subscripts c and m represent the fracture system and the matrix system, respectively; P ci represents the fracture system pressure in zone i; P mi represents the matrix system pressure in zone i; P 0 Indicates the original formation pressure; ΔP ci =P 0 -P ci ; ΔP mi =P 0 -P mi ; Q is the oil well production; t is the production time; h is the reservoir thickness; μ i is the viscosity of the fluid in zone i; φ ci is the porosity of the fracture system in zone i; φ mi is the porosity of the matrix system in zone i; K chi is the horizontal permeability of the fracture system in zone i; K cvi is the vertical permeability of the fracture system in zone i; K mhi is the horizontal permeability of the matrix system in zone i; K mvi is the vertical permeability of the matrix system in zone i; C cti is the comprehensive compression coefficient of the crack system in zone i; C mti is the comprehensive compressibility coefficient of the matrix system in zone i; B is the fluid volume coefficient; Z w is the distance from the horizontal well to the reservoir bottom; ε is the vertical length; β mi is the reservoir matrix system shape factor of the i-th zone; C is the wellbore storage coefficient; R e Is the outer border radius.

[0142] Step 4: Perform Laplace transformation on the shale oil reservoir heating development and transformation scope and permeability mathematical model through dimensionless variables, which specifically includes the following contents:

[0143] Define a dimensionless variable:

[0144] Dimensionless pressure:

[0145]

[0146]

[0147] Dimensionless production time:

[0148]

[0149] Dimensionless wellbore storage coefficient:

[0150]

[0151] Dimensionless radial. Horizontal distance:

[0152]

[0153] Dimensionless vertical distance:

[0154]

[0155] Dimensionless horizontal well length:

[0156]

[0157] Pressure conductivity ratio:

[0158]

[0159] Mobility ratio:

[0160]

[0161] Crossflow coefficient:

[0162]

[0163] Fracture system storage ratio:

[0164]

[0165] Matrix system storage ratio:

[0166]

[0167] Step 5

[0168] The Laplace transform is used to solve the heating development and transformation range and permeability mathematical model of shale oil reservoir under the infinite boundary, which specifically includes the following contents:

[0169] The dimensionless bottom hole pressure solution of a horizontal well under infinite boundary is:

[0170]

[0171] Where:

[0172]

[0173] e n1 =f 1(e)e+(nπL D1 ) 2

[0174]

[0175]

[0176] Step 6

[0177] The Laplace transform is used to solve the heating development and transformation scope and permeability mathematical model of the shale oil reservoir under the closed boundary, which specifically includes the following contents:

[0178] The dimensionless bottom hole pressure solution of a horizontal well under a closed boundary is:

[0179]

[0180] Where:

[0181]

[0182] Step 7

[0183] The Stehfest numerical inversion method is used for the pressure solution in the Lagrangian domain to obtain the pressure solution of the shale oil reservoir heating development and transformation range and the permeability mathematical model in the real domain.

[0184] The Laplace inverse transformation is performed on the pressure solution of the shale oil reservoir heating development and transformation scope and the permeability prediction model in the Laplace domain, namely:

[0185]

[0186] Step 8

[0187] Using the pressure solution of the horizontal well in the real domain and the actual pressure recovery test data, a double logarithmic curve of pressure recovery is drawn in a double logarithmic coordinate system with pressure and pressure derivative as the ordinate and time as the abscissa, as shown in Figure 3 (infinite boundary), Figure 4 (Closed boundary). By fitting the predicted double logarithmic curve with the actual double logarithmic curve, it can be seen that the transformation radius after heating and reforming in the horizontal well under the infinite boundary is 48.2m, and the permeability of the reformed area is 7.46mD; the transformation radius after heating and reforming in the horizontal well under the closed boundary is 51.3m, and the permeability of the reformed area is 8.74mD.

[0188] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for calculating the heating transformation range and permeability of a shale oil reservoir, characterized in that: The following steps are involved: S1. Select appropriate medium-low maturity shale oil reservoirs, design heating transformation methods in the heating development process of shale oil reservoirs, and construct a horizontal well heating model for shale oil reservoirs; S2. Establishing a shale oil reservoir heating development and transformation scope and a permeability physical model based on the production history data of the shale oil reservoir selected in S1; S3. Based on the shale oil reservoir heating development and transformation scope and permeability physical model constructed in S2, a shale oil reservoir heating development and transformation scope and permeability mathematical model is established to calculate the bottom hole pressure solution of the horizontal well; specifically, the following contents are included: S3.

1. Establishing a shale oil reservoir heating development and transformation scope and a permeability mathematical model based on the physical model; S3.2, Laplace transformation is performed on the shale oil reservoir heating development and transformation range and permeability mathematical model by dimensionless variables, and a semi-analytical method is used to solve the shale oil reservoir heating development and transformation range and permeability mathematical model obtained in S3.1 to obtain the bottom hole pressure solution of the horizontal well in the Laplace domain; S3.3, using the Stehfest numerical inversion method for the bottom hole pressure solution of the horizontal well in the Laplace domain obtained in S3.2, the pressure solution of the shale oil reservoir heating development and transformation range and the permeability mathematical model under two boundary conditions in the real domain is obtained; S4. Compare the pressure solution calculated in S3 with the actual pressure after heating to determine the heating transformation range and the permeability of the transformation area.

2. The method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 1, characterized in that: The heating transformation method in the shale oil reservoir heating development process described in S1 includes the following contents: S1.

1. Select a suitable medium-low maturity shale oil reservoir and drill a horizontal well into the shale oil reservoir; S1.2, install several electromagnetic heating devices at equal intervals on the wellbore of the horizontal well to heat the shale oil reservoir, and lead them out of the wellhead through cables; S1.

3. Power the wellhead cable and heat the shale oil reservoir to 400-500°C through an electromagnetic heating device to promote rapid maturation of organic matter in the shale oil reservoir, promote fracturing and reduce viscosity.

3. The method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 1, characterized in that: The shale oil reservoir heating development and transformation scope and permeability physical model described in S2 includes an infinite shale oil reservoir heating development and transformation scope and permeability physical model and a closed boundary shale oil reservoir heating development and transformation scope and permeability physical model; wherein, the assumptions of the infinite shale oil reservoir heating development and transformation scope and permeability physical model include: (1) Horizontal wells are considered as linear sources and produce at a fixed rate, with infinite horizontal diversion; (2) The fluid flow in shale oil reservoirs belongs to late pseudo-planar radial flow; (3) Both the inner and outer zones of the shale oil reservoir are fracture-matrix dual media; (4) During the heating transformation process, the fluid flows in a single phase and satisfies Darcy's law; (5) Ignore the effects of gravity and capillary forces; (6) Consider the skin effect S and the wellbore reservoir effect C; (7) The horizontal and vertical permeabilities of the reservoir are different; The assumptions of the closed boundary physics model are the same as those of the infinite size physics model except that the boundary is a closed boundary.

4. A method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 3, characterized in that: The scope of shale oil reservoir heating development and transformation and the permeability mathematical model specifically include the following contents: (1) Control equation of the inner zone crack system: (2) Control equation of the inner zone matrix system: (3) Control equation of the external zone crack system: (4) Control equation of the outer zone matrix system: (5) Boundary conditions of the transformation area: (6) Infinite boundary conditions in the outer region: ΔP c2 (R→∞,t)=0 (7) External closed boundary conditions: (8) Continuous boundary conditions between the transformation area and the external area: ΔP c1 (R1,t)=ΔP c1 (R1,t) (9) Initial conditions of the transformation area and the external area: ΔP ci | t＝0 =0 (i=1,2) ΔP mi | t＝0 =0 (i=1,2) Wherein, subscripts 1 and 2 represent the reformed area and the unreformed area, respectively; subscripts c and m represent the fracture system and the matrix system, respectively; P ci represents the fracture system pressure in zone i; P mi represents the matrix system pressure in the i-th zone; P0 represents the original formation pressure; ΔP ci =P0-P ci ; ΔP mi =P0-P mi ; Q is the oil well production; t is the production time; h is the reservoir thickness; μ i is the viscosity of the fluid in zone i; φ ci is the porosity of the fracture system in zone i; φ mi is the porosity of the matrix system in zone i; K chi is the horizontal permeability of the fracture system in zone i; K cvi is the vertical permeability of the fracture system in zone i; K mhi is the horizontal permeability of the matrix system in zone i; K mvi is the vertical permeability of the matrix system in zone i; C cti is the comprehensive compression coefficient of the crack system in zone i; C mti is the comprehensive compressibility coefficient of the matrix system in zone i; B is the fluid volume coefficient; Z w is the distance from the horizontal well to the reservoir bottom; ε is the vertical length; β mi is the reservoir matrix system shape factor of the i-th zone; C is the wellbore storage coefficient; R e Is the outer border radius.

5. A method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 4, characterized in that: The dimensionless variable technique is used to simplify the mathematical model and define the dimensionless variable: (1) Dimensionless pressure: (2) Dimensionless production time: (3) Dimensionless wellbore storage coefficient: (4) Dimensionless radial and horizontal distances: (5) Dimensionless vertical distance: (6) Dimensionless horizontal well length: (7) Pressure conductivity ratio: (8) Mobility ratio: (9) Crossflow coefficient: (10) Fracture system storage ratio: (11) Matrix system storage ratio:

6. A method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 5, characterized in that: The Laplace transform is used to solve the heating development and transformation range and permeability mathematical model of shale oil reservoir under the infinite boundary, which specifically includes the following contents: The dimensionless bottom hole pressure solution of a horizontal well under infinite boundary is: Where: Where: e is the Laplace variable; I0(x) and I1(x) are the first-order zero-order and first-order Bessel functions, respectively; K0(x) and K1(x) are the second-order zero-order and first-order Bessel functions, respectively.

7. A method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 6, characterized in that: The Laplace transform is used to solve the heating development and transformation scope and permeability mathematical model of the shale oil reservoir under the closed boundary, which specifically includes the following contents: The dimensionless bottom hole pressure solution of a horizontal well under a closed boundary is: Where:

8. A method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 7, characterized in that: S3.3 specifically includes the following contents: The Laplace inverse transformation is performed on the pressure solution of the shale oil reservoir heating development and transformation scope and the permeability prediction model in the Laplace domain: Given u and t, calculate P wD The value is obtained, and the scope of shale oil reservoir heating development and transformation and the pressure solution of the permeability prediction model in the real domain are obtained.

9. The method for calculating the heating transformation range and permeability of a shale oil reservoir according to claim 1, characterized in that: The S4 specifically includes the following contents: S4.

1. Using the pressure solution of the horizontal well in the real domain and the actual pressure recovery data, a double logarithmic curve of pressure recovery is drawn in a double logarithmic coordinate system with pressure and pressure derivative as the ordinate and time as the abscissa; S4.

2. Determine the R under two boundary conditions by fitting the predicted double logarithmic curve with the actual double logarithmic curve. D1 , R D1 The heating transformation range is determined, and the permeability of the transformation area after heating is further determined.

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