A method for quantitatively evaluating a carbonate rock strike-slip fault zone based on three-dimensional seismic data

Abstract

The present application belongs to the technical field of oil exploration, and relates to a quantitative evaluation method of super-deep carbonate strike-slip fault zone based on three-dimensional seismic data. The method comprises the following steps: S1: obtaining three-dimensional seismic original data of super-deep strike-slip fault zone, extracting and calculating Fault likehood seismic attribute value; obtaining oil and gas testing data; S2: establishing a strike-slip fault zone sample point database; S3: calculating hydrocarbon source stratum deformation intensity I; S4: determining weak-medium threshold and medium-strong threshold of source intensity; S5: establishing a fitting function expression relationship between each hydrocarbon source stratum deformation intensity I and oil and gas testing data, as a quantitative evaluation mathematical model of source intensity; S6: quantitatively evaluating the source intensity of super-deep carbonate strike-slip fault zone. The present application can qualitatively and quantitatively evaluate the source intensity of strike-slip fault, so as to realize the rapid optimization of the favorable area of super-deep carbonate reservoir formation in the area with limited data and few wells.

Description

Technical Field

[0001] This invention belongs to the field of petroleum exploration technology and relates to a quantitative evaluation method for the source of ultra-deep carbonate strike-slip fault zones based on three-dimensional seismic data. Background Technology

[0002] Ultra-deep carbonate rocks possess abundant oil and gas resources and are considered an important successor area for oil and gas exploration in China. In recent years, ultra-deep carbonate rock fault-dissolved and fault-controlled fracture-vuggy oil and gas reservoirs have been discovered in the Middle and Lower Ordovician strata of the Tarim Basin, making strike-slip fault zones within the craton another research hotspot with broad exploration prospects. Strike-slip faults play a crucial role in controlling the migration, accumulation, and preservation of oil and gas in Ordovician carbonate rocks, and also have a significant constructive effect on carbonate reservoirs. High-quality oil and gas reservoirs are mainly distributed in strike-slip fault fracture zones, forming complex and diverse carbonate oil and gas reservoirs controlled by strike-slip fault fracture zones.

[0003] The connectivity of strike-slip fault zones in ultra-deep carbonate rocks refers to the extent to which these faults connect with the main source strata of hydrocarbons, i.e., whether the strike-slip fault zone connects with the main source strata and the degree to which it cuts through them. The connectivity of strike-slip fault zones in ultra-deep carbonate rocks is the material basis for hydrocarbon accumulation and a crucial factor influencing hydrocarbon migration and accumulation in ultra-deep carbonate rocks.

[0004] Existing assessments of the source potential of ultra-deep carbonate strike-slip fault zones face challenges, particularly in quantitative evaluation, due to limited well data and limited data sources (seismic data only). The structural style method primarily relies on the morphology of seismic reflection phase axes, amplitude properties, and fault zone structure, combined with statistical analysis of oil, gas, and water production from actual drilled wells, to qualitatively evaluate the source potential of strike-slip fault zones. This method depends on detailed interpretation of 3D seismic data, especially the identification of the contact relationship between low-order strike-slip faults and source strata on seismic profiles. Furthermore, it can only provide a qualitative spatial relationship between strike-slip fault zones and source strata, failing to achieve quantitative evaluation. The geometric method for strike-slip fault zones is based on the premise that faults act as channels for oil and gas migration, with their longitudinal extension and width representing, to some extent, the source potential. However, this method focuses on the geometric characteristics of the strike-slip fault zone itself, neglecting the degree of deformation in the source strata caused by small-scale slip distances. Field geological surveys are also a common method for evaluating the sourceness of strike-slip fault zones. However, for ultra-deep carbonate strike-slip fault zones, field surveys are costly and require specific conditions, making it difficult to achieve a rapid and economical quantitative evaluation of sourceness. Overall, in areas with limited data and few wells in ultra-deep carbonate strike-slip fault zones, the main problem in evaluating sourceness is currently relying solely on 3D seismic data interpretation to describe structural styles and geometric features, combined with only qualitative evaluations of sourceness through field geological surveys.

[0005] Zhang Yanqiu, Chen Honghan, Wang Xiepei, et al., published their work in the journal *Petroleum and Gas Geology* on the source connectivity evaluation of the strike-slip fault zone in the Fuman Oilfield of the Tarim Basin. This technical approach, based on 3D seismic data, utilizes the Riedel shear discrete element model and the fully plastic medium-stress rise function model to evaluate the oil source connectivity of the FI17 strike-slip fault zone in Block II of the Fuman Oilfield in the Tarim Basin. However, while the Riedel shear discrete element model can simulate the geometric characteristics and mechanical behavior of the fault zone, its assumptions (such as material properties and boundary conditions) may deviate from reality. Furthermore, the fully plastic medium-stress rise function model assumes a fully plastic medium and uses a specific stress rise function, which may oversimplify actual geological conditions. Summary of the Invention

[0006] The purpose of this invention is to provide a quantitative evaluation method for the source connectivity of ultra-deep carbonate strike-slip fault zones based on 3D seismic data. This method achieves a qualitative to quantitative evaluation of the source connectivity of ultra-deep carbonate strike-slip fault zones, comprehensively considering the structural style, geometric characteristics, and hydrocarbon source strata deformation characteristics of the strike-slip fault zones based on 3D seismic data. This enables rapid selection of favorable hydrocarbon accumulation zones in areas with limited data on ultra-deep carbonate strike-slip fault zones and few wells.

[0007] The above-mentioned objective of this invention is achieved through the following technical solution:

[0008] This invention provides a method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones based on three-dimensional seismic data, comprising the following steps:

[0009] Step S1: Obtain the original 3D seismic data volume of the ultra-deep strike-slip fault zone and extract and calculate the fault.

[0010] Likehood earthquake attribute values; obtain oil and gas test data;

[0011] Step S2: Extract a cross-section perpendicular to the strike-slip fault zone and establish a database of strike-slip fault zone sample points;

[0012] Step S3: Determine the deformation width W of the source stratum caused by the strike-slip fault zone at the contact point with the source stratum at each sampling point, the undulating deformation height H of the source stratum, and calculate the deformation intensity I of the source stratum.

[0013] Step S4: Establish the probability density distribution function and cumulative probability curve overlay diagram of the deformation intensity I of the source strata, and determine the weak-medium threshold and medium-strong threshold of the source intensity.

[0014] Step S5: Fit the deformation intensity I of the source formation with the oil and gas test data, establish the linear fitting, quadratic fitting, logarithmic fitting and exponential fitting function relationship between the deformation intensity I of each source formation and the oil and gas test data, and select the expression with the largest correlation coefficient as the mathematical model for quantitative evaluation of sourceability.

[0015] Step S6: Use a mathematical model for quantitative evaluation of source connectivity to quantitatively evaluate the source connectivity of strike-slip fault zones in ultra-deep carbonate rocks.

[0016] Preferably, in step S1, the original three-dimensional seismic data volume of the ultra-deep strike-slip fault zone is obtained from the geophysical exploration database of the oilfield.

[0017] Preferably, in step S1, DSG seismic interpretation software is used to extract and calculate the fault likehood (maximum likelihood) seismic attribute values.

[0018] Preferably, the formula for calculating the Fault Likehood seismic attribute value in step S1 is:

[0019]

[0020] likelihood(x,y,τ)=1-C(x,y,τ) n

[0021]

[0022] In the formula, C(τ, p, q) is the average similarity coefficient of seismic data gathers, dimensionless; τ represents the specific time window of analysis, in ms; p and q represent the apparent dip angles in the x and y directions, respectively, in °; K=ω / △t is the number of gathers within the time window length (2ω+1) ms, dimensionless; △t is the seismic data sampling interval, in ms; x j y j These represent the distances of the j-th seismic data point from the center point on the x and y axes, respectively, in meters (m). The subscript j indicates the j-th seismic data point within the analysis window. px j ,qy j This represents the time shift of the j-th seismic trace relative to the center point in the time direction, in milliseconds; the superscript H indicates that a Hilbert transform is performed on the seismic trace; J represents the number of seismic traces within the τ time window; it is dimensionless; n is set to 8 to amplify the difference between high and low similarity coefficient values, and it is dimensionless. θ represents the dip angle of the tomographic scan, in degrees (°), and θ represents the dip angle of the tomographic scan section, in degrees (°).

[0023] The above Fault Likehood seismic attribute values ​​can be automatically calculated using DSG seismic processing and interpretation software.

[0024] Preferably, in step S1, the test oil and gas data are obtained from the single-well production database of the oilfield.

[0025] Preferably, the pilot oil and gas data in step S1 is the average daily oil and gas production in the initial stage of the production phase.

[0026] Preferably, in step S2, the cross-section perpendicular to the strike-slip fault zone is cut at intervals of 1 km along the strike-slip fault zone.

[0027] The principle of determining the stratigraphic deformation width W and stratigraphic undulation height H caused by the strike-slip fault zone at the contact point with the source rock strata in this invention is that the extracted fault likeness seismic attribute will produce abnormally high values ​​at the strike-slip fault zone.

[0028] Preferably, step S3 specifically includes the following steps:

[0029] Step S31: Based on the extracted Fault likehood seismic attribute values, use Petrel to extract the Fault likehood layer attribute values ​​of the source strata along the direction perpendicular to the strike-slip fault zone;

[0030] Step S32: Assign the extracted Fault Likehood layer attribute values ​​of the source strata to a series of sample points to obtain the attribute values ​​of each sample point;

[0031] Step S33: Draw a scatter plot, observe the anomalous attribute values ​​at the core zone of the strike-slip fault along the envelope of the scatter plot, obtain the deformation width W of the source strata, measure the apparent height L of the deformation undulation of the source strata on the intercepted profile, the angle α between the principal axis of the deformation undulation of the source strata and the vertical direction, and calculate the degree of deformation I of the source strata. The calculation formula is as follows:

[0032] W = X2 - X1

[0033] H=Lcosα

[0034]

[0035] In the formula, I represents the deformation intensity of the source strata caused by the strike-slip fault, which is dimensionless; H represents the true height of the strata deformation undulation, and L represents the apparent height of the strata deformation undulation, both in meters; W represents the strata deformation width, in meters; X2 represents the high value of the scatter plot of the strata deformation range attribute value caused by the strike-slip fault zone, and X1 represents the low value, both in meters.

[0036] Preferably, step S31 specifically involves dividing a series of 20 sample points along the direction perpendicular to the strike-slip fault zone at intervals of 0.5 km, importing the extracted Fault Likehood seismic attribute values ​​into Petrel, and extracting the Fault Likehood layer attribute values ​​of the source strata.

[0037] Preferably, step S32 specifically involves assigning the extracted Fault Likehood layer attribute values ​​of the source strata to 20 sample points to obtain the attribute values ​​of each sample point.

[0038] Preferably, step S4 specifically involves: forming a sample point database along the strike-slip fault zone using the calculated hydrocarbon source deformation intensity I; plotting the probability density distribution function and cumulative probability curve overlay diagram of the calculated hydrocarbon source strata deformation intensity I in Origin; and determining the weak-medium threshold and medium-strong threshold for source intensity.

[0039] Preferably, the weak-to-medium threshold for the source strength in step S4 is the cumulative probability of 50% in the superposition graph of the probability density distribution function and the cumulative probability curve.

[0040] Preferably, in step S4, the medium-strong threshold of the source strength is the point where the cumulative probability is 100% in the superposition graph of the probability density distribution function and the cumulative probability curve.

[0041] Preferably, step S5 specifically involves: using the source formation deformation intensity I as the horizontal axis and the average daily oil and gas production Q in the initial stage of production as the vertical axis, drawing a scatter plot using Excel software, selecting scatter points and fitting trend lines, and establishing linear, quadratic, logarithmic, and exponential fitting functions to express the relationship between the source formation deformation intensity I and the average daily oil and gas production Q in the initial stage of production. The expression with the largest correlation coefficient between the source formation deformation intensity I and the average daily oil and gas production Q in the initial stage of production is used as the mathematical model for quantitatively evaluating the sourceability.

[0042] Preferably, the correlation coefficient is calculated using the following formula:

[0043]

[0044] In the formula, R is the correlation coefficient, and Ik is the deformation intensity I parameter value of the source stratum at the kth sampling point; Qk is the average value of the deformation intensity I data of the source formation at all sampling points; Qk is the average daily oil and gas production Q value at the k-th sampling point during the initial stage of production. This represents the average daily oil and gas production Q at all sample points during the initial stage of the production phase.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] This invention integrates 3D seismic data of ultra-deep carbonate rocks, single-well production test data, and gas production test data to establish a novel quantitative evaluation method for the source connectivity of strike-slip fault zones in ultra-deep carbonate rocks, which has the following advantages:

[0047] (1) The fusion of the original three-dimensional seismic data volume and the Fault likehood seismic attributes can effectively characterize the contact relationship between small-scale slip distance strike-slip fault zones and hydrocarbon source strata, making up for the shortcomings of insufficient accuracy of amplitude seismic attributes.

[0048] (2) This method fully considers the degree of deformation of the source strata caused by the small-scale slip distance strike-slip fault zone under geological conditions, clarifies the activity intensity of the strike-slip fault zone, and makes the method more scientific by analyzing the correlation with the actual production single well oil and gas test, thus avoiding the influence of human factors.

[0049] (3) Combining the probability density distribution function of the deformation intensity I of the source strata and the superposition diagram of the cumulative probability curve, this method can achieve qualitative and quantitative evaluation of the source nature of strike-slip faults, thereby enabling rapid selection of favorable areas for hydrocarbon accumulation in ultra-deep carbonate rock areas with limited data and few wells. Attached Figure Description

[0050] Figure 1 This is a flowchart of a quantitative evaluation method for the source of ultra-deep carbonate strike-slip fault zones based on three-dimensional seismic data, according to Embodiment 1 of the present invention.

[0051] Figure 2 This is a calculation diagram of the fault likeness attribute extraction for key layers of the strike-slip fault zone in Embodiment 1 of the present invention;

[0052] Figure 3 This is a cross-sectional view and distribution diagram of the strike-slip fault zone sampling points in Example 1 of the present invention;

[0053] Figure 4 This is a schematic diagram illustrating how the deformation width W and undulation height H of the strike-slip fault zone are determined using the Fault likehood attribute value in Embodiment 1 of the present invention.

[0054] Figure 5 This is a superimposed diagram of the probability density distribution function and cumulative probability curve of the deformation intensity I of the hydrocarbon source stratum in Example 1 of the present invention;

[0055] Figure 6 This is a strength evaluation diagram of the source of the strike-slip fault zone in Embodiment 1 of the present invention;

[0056] Figure 7 This is a graph showing the exponential function relationship between the source formation deformation intensity I and the average daily oil and gas production (test gas data) Q in the initial stage of the production phase, according to Example 1 of the present invention.

[0057] Figure 8 This is a linear function relationship between the source formation deformation intensity I and the average daily oil and gas production (test gas data) Q in the early stage of the production phase in Example 1 of the present invention.

[0058] Figure 9 This is a logarithmic function relationship between the source formation deformation intensity I and the average daily oil and gas production (test gas data) Q in the initial stage of the production phase in Example 1 of the present invention.

[0059] Figure 10 This is a quadratic function relationship between the source formation deformation intensity I and the average daily oil and gas production (test gas data) Q in the early stage of the production phase in Example 1 of the present invention. Detailed Implementation

[0060] The following non-limiting embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way. The following description is merely an exemplary illustration of the scope of protection of the present invention, and those skilled in the art can make various changes and modifications to the invention based on the disclosed content, which should also fall within the scope of protection of the present invention.

[0061] The present invention will be further described below by way of specific embodiments.

[0062] Example 1

[0063] A quantitative evaluation method for the source of ultra-deep carbonate strike-slip fault zones based on 3D seismic data, such as... Figure 1 As shown, it includes the following steps:

[0064] Step S1: Obtain the original 3D seismic data volume of the ultra-deep strike-slip fault zone from the geophysical exploration database of the oilfield, and use DSG seismic interpretation software to extract and calculate the fault likehood seismic attribute value. The calculation results are as follows: Figure 2 As shown in Table 1, the average daily oil and gas production during the initial stage of the production phase was obtained from the single-well production database of the oilfield.

[0065] Table 1

[0066] well name <![CDATA[X1 / m]]> <![CDATA[X2 / m]]> L / m α / ° W / m H / m SHB81X 4010.52 5005.49 25.65 7.86 994.97 187.64 SHB82X 4100.25 8237.56 27.10 4.70 4137.31 330.88 SHB803X 4205.6 4926.26 306.21 30.50 720.66 603.59 SHB801X 4079.5 5622.46 556.72 25.78 1542.96 1280.66 SHB8X 4126.36 7112.77 166.01 11.44 2986.41 837.41 SHB802X 4136.35 8915.62 300.52 10.55 4779.27 1642.14 SHB83X 4015.6 7319.99 417.08 19.07 3304.39 1277.17 SHB84X 4108.36 6018.79 52.48 1.76 1910.43 1709.58 SHB85X 3985.22 6783.1 195.3 9.98 2797.88 1127.66

[0067] The formula for calculating the Fault Likehood earthquake attribute value is as follows:

[0068]

[0069] likelihood(x,y,τ)=1-C(x,y,τ) n

[0070]

[0071] In the formula, C(τ, p, q) is the average similarity coefficient of seismic data gathers, dimensionless; τ represents the specific time window of analysis, in ms; p and q represent the apparent dip angles in the x and y directions, respectively, in °; K=ω / △t is the number of gathers within the time window length (2ω+1) ms, dimensionless; △t is the seismic data sampling interval, in ms; x j y j These represent the distances of the j-th seismic data point from the center point on the x and y axes, respectively, in meters (m). The subscript j indicates the j-th seismic data point within the analysis window. px j ,qy j This represents the time shift of the j-th seismic trace relative to the center point in the time direction, in milliseconds; the superscript H indicates that a Hilbert transform is performed on the seismic trace; J represents the number of seismic traces within the τ time window; it is dimensionless; n is used to amplify the difference between high and low values ​​of the similarity coefficient, and is generally set to 8, which is also dimensionless. The value represents the fault scan dip, in degrees (°), and θ represents the fault scan section dip angle, also in degrees (°). The results can be automatically calculated using DSG seismic processing and interpretation software.

[0072] Step S2: Along the strike-slip fault zone, cross sections perpendicular to the fault zone are taken at 1km intervals to establish a database of strike-slip fault zone sampling points, such as... Figure 3 The sample point division is shown.

[0073] Step S3: Calculate the deformation width of the source strata caused by the small-scale strike-slip fault zone at each sampling point. A schematic diagram of the specific operation is shown below. Figure 4 As shown.

[0074] Step S31: Along the direction perpendicular to the strike-slip fault zone, with the strike-slip fault zone characterized by the Fault likehood seismic attribute as the center, divide the series of 20 sampling points at intervals of 0.5km, import the extracted Fault likehood seismic attribute values ​​into Petrel, and extract the Fault likehood layer attribute values ​​of the source strata.

[0075] Step S32: Assign the extracted hydrocarbon source layer attribute values ​​to 20 sample points and export them to an Excel spreadsheet;

[0076] Step S33: Plot a scatter plot, such as... Figure 4 As shown, the scatter plot envelope is drawn. At the turning point between the two straight segments of the envelope, the deformation width W of the source strata caused by the fault zone is determined. This means that the Faultlikehood seismic attribute transitions from the surrounding rock to the fault core zone, and the Faultlikehood seismic attribute value begins to increase. After determining the deformation width W of the source strata, the apparent height L of the deformation undulation of the source strata is measured on the seismic profile, and the angle α between it and the vertical direction is calculated. The deformation intensity I of the source strata is also calculated using the following formula:

[0077] W = X2 - X1

[0078] H=Lcosα

[0079]

[0080] In the formula, I represents the deformation intensity of the source strata caused by the strike-slip fault, which is dimensionless; H represents the true height of the deformation undulation of the source strata, and L represents the apparent height of the deformation undulation of the source strata, both in meters; W represents the deformation width of the source strata, in meters; X2 represents the high value of the scatter plot of the deformation range attribute value caused by the strike-slip fault zone, and X1 represents the low value, both in meters.

[0081] Step S4: The calculated deformation intensity I of the source strata along the strike of the strike-slip fault zone is used to form a sample point database. In Origin, the probability density distribution function and cumulative probability curve overlay are plotted for the calculated source strata deformation intensity I at certain step intervals. The weak-medium and medium-strong thresholds for source intensity are determined at cumulative probability levels of 50% and 100%. Figure 5 and Figure 6 As shown.

[0082] Step S5: Using the source formation deformation intensity I as the horizontal axis and the average daily oil and gas production Q in the early stage of production as the vertical axis, draw a scatter plot using Excel software, select scatter points and fit a trend line, and establish linear, quadratic, logarithmic, and exponential fitting functions to express the relationship between the source formation deformation intensity I and the average daily oil and gas production Q in the early stage of production. The relationship with the largest correlation coefficient between the source formation deformation intensity I and the average daily oil and gas equivalent Q in the early stage of production is used as the mathematical model for quantitatively evaluating the sourceability, and is denoted as the IQ mathematical model.

[0083] The formula for calculating the correlation coefficient is as follows:

[0084]

[0085] In the formula, R is the correlation coefficient, and Ik is the deformation intensity I parameter value of the source stratum at the kth sampling point; Qk is the average value of the deformation intensity I data of the source formation at all sampling points; Qk is the average daily oil and gas production Q value at the k-th sampling point during the initial stage of production. This represents the average daily oil and gas production Q at all sample points during the initial stage of the production phase.

[0086] like Figure 7-10The figure shown is a functional relationship between the source rock deformation intensity I and the average daily oil and gas production Q in the early stage of the strike-slip fault zone in this embodiment. It can be found that the source rock deformation intensity I affects the oil and gas production of ultra-deep carbonate rocks to a certain extent, indicating that the use of source rock deformation intensity I to characterize the source rock source is effective in this study.

[0087] Compare the correlation coefficients between the source formation deformation intensity I and the average daily oil and gas production Q in the initial stage of production under different fitting functions, such as... Figure 7-10 Tables 2 and 3.

[0088] Table 2

[0089] Fitting type R Exponential Fit 0.5788 Linear fitting 0.592 Log-fit 0.5985 Quadratic fitting 0.5967

[0090] Table 3

[0091] well name I Q(t / d) SHB81X 0.19 367.20 SHB82X 0.08 233.10 SHB803X 0.84 567.50 SHB801X 0.83 794.00 SHB8X 0.28 627.00 SHB802X 0.34 613.00 SHB83X 0.39 283.59 SHB84X 0.89 853.00 SHB85X 0.40 505.00

[0092] The mathematical model of IQ obtained by fitting an exponential function is: y = 297.28e 1.0843x ,

[0093] R 2 =0.5788;

[0094] The mathematical model of IQ obtained by fitting a linear function is: y = 541.62x + 282.63.

[0095] R 2 =0.592;

[0096] The mathematical model of IQ obtained by fitting a logarithmic function is: y = 209.75lnx + 744.79.

[0097] R 2 =0.5985;

[0098] The mathematical model of IQ obtained by fitting a quadratic function is: y = -243.56x 2 +797.17x+236.34, R 2 =0.5967.

[0099] It can be seen that the correlation coefficients of the various functions are not significantly different, all around 0.59. Among them, the logarithmic function shows the strongest correlation with the IQ mathematical model, with R0. 2 =0.5985, further verifying the effectiveness of the mathematical model for characterizing source formation deformation intensity I and the average daily oil and gas production Q in the early stage of production.

[0100] This model can be used to quantitatively evaluate the source of other strike-slip fault zones and obtain the source variation of ultra-deep carbonate strike-slip fault zones in the study area.

[0101] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones based on three-dimensional seismic data, characterized in that, Includes the following steps: Step S1: Obtain the original 3D seismic data volume of the ultra-deep strike-slip fault zone and extract and calculate the Fault Likehood seismic attribute value; Obtain test gas data; Step S2: Extract a cross-section perpendicular to the strike-slip fault zone and establish a database of strike-slip fault zone sample points; Step S3: Determine the deformation width W of the source stratum caused by the strike-slip fault zone at the contact point with the source stratum at each sampling point, the undulating deformation height H of the source stratum, and calculate the deformation intensity I of the source stratum. Step S4: Establish the probability density distribution function and cumulative probability curve overlay diagram of the deformation intensity I of the source strata, and determine the weak-medium threshold and medium-strong threshold of the source intensity. Step S5: Fit the deformation intensity I of the source formation with the oil and gas test data, establish the linear fitting, quadratic fitting, logarithmic fitting and exponential fitting function relationship between the deformation intensity I of each source formation and the oil and gas test data, and select the expression with the largest correlation coefficient as the mathematical model for quantitative evaluation of sourceability. Step S6: Use a mathematical model for quantitative evaluation of source connectivity to quantitatively evaluate the source connectivity of strike-slip fault zones in ultra-deep carbonate rocks.

2. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 1, characterized in that, The formula for calculating the Fault Likehood seismic attribute value in step S1 is: likelihood(x,y,τ) = 1 - C(x,y,τ) n In the formula, C(τ, p, q) is the average similarity coefficient of seismic data gathers, dimensionless; τ represents the specific time window of analysis, in ms; p and q represent the apparent dip angles in the x and y directions, respectively, in °; K=ω / △t is the number of gathers within the time window length (2ω+1) ms, dimensionless; △t is the seismic data sampling interval, in ms; x j y j These represent the distances of the j-th seismic data point from the center point on the x and y axes, respectively, in meters (m). The subscript j indicates the j-th seismic data point within the analysis window. px j ,qy j The time shift of the j-th seismic data point relative to the center point is expressed in milliseconds (ms). The superscript H indicates that a Hilbert transform is applied to the seismic trace. J represents the number of seismic data points within the τ time window; it is dimensionless. n is set to 8 to amplify the difference between high and low similarity coefficients; it is dimensionless. φ represents the fault scan dip in degrees (°), and θ represents the fault scan dip angle in degrees (°).

3. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 2, characterized in that, The pilot oil and gas data in step S1 is the average daily oil and gas production during the initial stage of production.

4. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 3, characterized in that, In step S2, the cross-section perpendicular to the strike-slip fault zone is cut at intervals of 1 km along the strike-slip fault zone.

5. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 4, characterized in that, Step S3 includes the following specific steps: Step S31: Based on the extracted Fault likehood seismic attribute values, use Petrel to extract the Fault likehood layer attribute values ​​of the source strata along the direction perpendicular to the strike-slip fault zone; Step S32: Assign the extracted Fault Likehood layer attribute values ​​of the source strata to a series of sample points to obtain the attribute values ​​of each sample point; Step S33: Draw a scatter plot, observe the anomalous attribute values ​​at the core zone of the strike-slip fault along the envelope of the scatter plot, obtain the deformation width W of the source strata, measure the apparent height L of the deformation undulation of the source strata on the intercepted profile, the angle α between the principal axis of the deformation undulation of the source strata and the vertical direction, and calculate the degree of deformation I of the source strata. The calculation formula is as follows: W = X2 - X1 H=Lcosα In the formula, I represents the deformation intensity of the source strata caused by the strike-slip fault, which is dimensionless; H represents the true height of the deformation undulation of the source strata, and L represents the apparent height of the deformation undulation of the source strata, both in meters; W represents the deformation width of the source strata, in meters; X2 represents the high value of the scatter plot of the deformation range attribute value caused by the strike-slip fault zone, and X1 represents the low value, both in meters.

6. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 5, characterized in that, Step S31 specifically involves dividing the sample points into 20 series at 0.5km intervals along the direction of the vertical strike-slip fault zone, importing the extracted Fault Likehood seismic attribute values ​​into Petrel, and extracting the Fault Likehood layer attribute values ​​of the source strata.

7. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 6, characterized in that, Step S4 specifically involves: forming a sample point database along the strike-slip fault zone using the calculated source strata deformation intensity I; plotting the probability density distribution function and cumulative probability curve overlay in Origin for the calculated source strata deformation intensity I; and determining the weak-medium and medium-strong thresholds for source intensity.

8. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 7, characterized in that, In step S4, the weak-medium threshold for source strength is the point where the cumulative probability of the superimposed graph of the probability density distribution function and the cumulative probability curve is 50%; the medium-strong threshold for source strength is the point where the cumulative probability of the superimposed graph of the probability density distribution function and the cumulative probability curve is 100%.

9. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 8, characterized in that, Step S5 specifically involves: using the source formation deformation intensity I as the horizontal axis and the average daily oil and gas production Q in the initial stage of production as the vertical axis, drawing a scatter plot using Excel software, selecting scatter points and fitting a trend line, and establishing linear, quadratic, logarithmic, and exponential fitting functions to express the relationship between the source formation deformation intensity I and the average daily oil and gas production Q in the initial stage of production. The expression with the largest correlation coefficient between the source formation deformation intensity I and the average daily oil and gas production Q in the initial stage of production is used as the mathematical model for quantitatively evaluating the sourceability.

10. The method for quantitatively evaluating the source of ultra-deep carbonate strike-slip fault zones according to claim 9, characterized in that, The formula for calculating the correlation coefficient is: In the formula, R is the correlation coefficient, and I k Let I be the deformation intensity parameter value of the source stratum at the k-th sampling point; Q is the average value of the deformation intensity I data of the source strata at all sampling points; k Let Q be the average daily oil and gas production value at the k-th sample point during the initial stage of the production phase. This represents the average daily oil and gas production Q at all sample points during the initial stage of the production phase.

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