Method for evaluating the transport capacity of an oil source fault, evaluation system and storage medium

Abstract

This invention provides a method, system, and storage medium for evaluating the transport capacity of oil-source faults, belonging to the field of oil and gas geological exploration. It includes: determining the hydrocarbon expulsion intensity of source rocks based on the source rock strata and organic matter characteristic parameters of the source rocks in the target study area; determining the vertical transport capacity of the oil-source fault based on the static rock pressure of the overlying strata, the regional principal compressive stress components, and the lower limit of pressure required for fault plane closure in the target study area; determining the lateral transport capacity of the oil-source fault based on the fault-sand contact length and fault gouge ratio; and determining fault transport capacity evaluation parameters based on the hydrocarbon expulsion intensity, vertical transport capacity, lateral transport capacity, and oil-source fault growth index. This invention, based on the influencing factors of fault transport capacity, quantitatively characterizes the comprehensive transport capacity of oil-source faults from multiple aspects, and can be used to predict the transport capacity of oil-source faults, helping to find favorable areas and strata for future oil and gas exploration.

Description

Technical Field

[0001] This invention relates to the field of oil and gas geological exploration technology, and specifically to a method, evaluation system, and storage medium for evaluating the conduction capacity of oil-source faults. Background Technology

[0002] Faults are the main channels for the vertical migration of oil and gas from deep to shallow layers. As an important bridge connecting traps and source rocks, they play a crucial role in the process of oil and gas accumulation. The strength of the fault's conductivity also affects the degree of oil and gas enrichment.

[0003] Existing technologies have conducted in-depth research on fault conductivity from multiple perspectives, discussing the controlling role of different geological factors on fault conductivity. However, most existing conductivity evaluation methods focus on the static geological elements of faults, and the consideration of dynamic hydrocarbon accumulation processes is still insufficient. Moreover, existing technologies often use a single index to evaluate fault conductivity, resulting in low accuracy in characterizing fault conductivity and failing to effectively quantify the comprehensive conductivity of oil-source fractures. Summary of the Invention

[0004] This invention provides a method, system, and storage medium for evaluating the transport capacity of oil-source faults, addressing, or at least partially addressing, the problems of incomplete consideration of fault-controlling factors and low accuracy in characterizing fault transport capacity. Based on factors influencing fault transport capacity, this method quantifies the comprehensive transport capacity of oil-source faults from multiple aspects, including the hydrocarbon supply capacity of the primary hydrocarbon-generating source rocks, the intensity of fault activity, the dynamics of hydrocarbon transport, and the degree of fault zone opening. This method can be used to predict the transport capacity of oil-source faults, aiding in the identification of favorable areas and strata for future oil and gas exploration.

[0005] The purpose of this invention is to provide a method for evaluating the transport capacity of oil-source faults. The method includes: determining the hydrocarbon expulsion intensity of the source rocks based on the source rock strata and organic matter characteristic parameters of the source rocks in a target study area, wherein the target study area is an area with fault-controlled reservoir characteristics; determining the vertical transport capacity of the oil-source fault based on the overlying strata static pressure, the regional principal compressive stress component, and the lower pressure limit required for fault plane closure in the target study area; determining the lateral transport capacity of the oil-source fault based on the fault-sand contact length and fault gouge ratio; and determining fault transport capacity evaluation parameters for evaluating the transport capacity of the oil-source fault based on the hydrocarbon expulsion intensity of the source rocks, the vertical transport capacity of the oil-source fault, the lateral transport capacity of the oil-source fault, and the oil-source fault growth index.

[0006] Optionally, the organic matter characteristic parameters include: thickness of different organic phase source rocks, organic matter abundance, and hydrogen index.

[0007] Optionally, determining the vertical transport capacity of the oil-source fault based on the static rock pressure of the overlying strata in the target study area, the regional principal compressive stress components, and the lower limit of pressure required for fault closure includes:

[0008] Based on the static rock pressure N1 of the overlying strata in the target study area, the regional principal compressive stress component N2, and the lower pressure limit N required for fault closure, ... min The vertical transport capacity F of the oil source fault is determined by the following formula. v :

[0009]

[0010] Optionally, the overlying strata static rock pressure N1, the regional principal compressive stress component N2, and the lower limit of pressure N required for fault closure are... min The following formula is used to determine:

[0011] N1=Z(ρ r -ρ w )g cosα

[0012] N2=σsinαsinβ

[0013] N min =0.0012ρ w gZ

[0014] In the formula, Z is the burial depth of the cross section; ρ r ρ is the average density of the overlying strata. w σ is the density of formation water; g is the gravitational acceleration; σ is the horizontal principal compressive stress; α is the dip angle of the fault section; β is the angle between the horizontal principal compressive stress and the fault strike.

[0015] Optionally, determining the lateral transport capacity of the oil-source fault based on the fault sand contact length and fault gouge ratio includes:

[0016] Based on the contact length L of the fault sand and the fault gouge ratio SGR, the lateral transport capacity F of the oil source fault is determined by the following formula. l :

[0017] F l =L(1-SGR).

[0018] Optionally, the contact length L of the fault sand and the fault gouge ratio SGR are determined by the following formula:

[0019]

[0020] In the formula, H i R represents the thickness of the i-th layer that has been faulted; idenoted as , where is the mud content of the i-th layer displaced by the fault; D is the vertical displacement of the fault; h is the sand body thickness; and θ is the sand body dip angle.

[0021] Optionally, the step of determining the fault conductivity evaluation parameters for evaluating the conductivity of the oil-source fault based on the hydrocarbon expulsion intensity of the source rock, the vertical conductivity of the oil-source fault, the lateral conductivity of the oil-source fault, and the growth index of the oil-source fault includes:

[0022] Based on the hydrocarbon expulsion intensity E of the source rock and the vertical transport capacity F of the oil source fault... v The lateral transport capacity F of the oil source fault l And the oil-source fault growth index Q, the fault conductivity evaluation parameter T is determined by the following formula:

[0023]

[0024] In the formula, H1 is the thickness of the hanging wall of the fault; H2 is the thickness of the footwall of the fault.

[0025] Optionally, after determining the fault conductivity evaluation parameters, the evaluation method further includes: verifying the fault conductivity evaluation parameters based on the actual oil and gas reservoir thickness of the well.

[0026] On the other hand, the present invention also provides an evaluation system for the transport capacity of oil-source faults. The evaluation system includes: a first parameter determination device for determining the hydrocarbon expulsion intensity of the source rock based on the source rock strata of the target study area and the organic matter characteristic parameters of the source rock, wherein the target study area is an area with fault transport control characteristics; a second parameter determination device for determining the vertical transport capacity of the oil-source fault based on the overlying strata static pressure, the regional principal compressive stress component, and the lower limit of pressure required for fault plane closure in the target study area; a third parameter determination device for determining the lateral transport capacity of the oil-source fault based on the fault sand contact length and the fault gouge ratio; and an evaluation parameter determination device for determining fault transport capacity evaluation parameters for evaluating the transport capacity of the oil-source fault based on the hydrocarbon expulsion intensity of the source rock, the vertical transport capacity of the oil-source fault, the lateral transport capacity of the oil-source fault, and the oil-source fault growth index.

[0027] In another aspect, this application provides a machine-readable storage medium storing instructions for causing a machine to execute: the evaluation method for the conduction capacity of an oil source fault as described above.

[0028] Through the above technical solutions, the evaluation method for the transmission capacity of oil-source faults proposed in this invention comprehensively considers multiple factors such as the hydrocarbon supply capacity of the main hydrocarbon source rocks during the main hydrocarbon accumulation period, the strength of fault activity, the driving force of oil and gas transmission, and the degree of opening of the fault zone. It quantitatively characterizes the comprehensive transmission capacity of oil-source faults and can be used to predict the transmission capacity of oil-source faults, which helps to find favorable areas and strata for future oil and gas exploration.

[0029] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0030] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0031] Figure 1 This is a flowchart illustrating a method for evaluating the transport capacity of an oil-source fault according to an embodiment of this application;

[0032] Figure 2 This is a flowchart illustrating a method for quantitatively evaluating the transport capacity of an oil-source fault according to an embodiment of this application;

[0033] Figure 3 This is a schematic diagram of the enclosed planar distribution of a certain region according to an embodiment of this application;

[0034] Figure 4 This is a schematic diagram illustrating the hydrocarbon emission intensity of a certain region according to an embodiment of this application;

[0035] Figures 5a-5b This is a schematic diagram illustrating the transmission pattern of a certain region according to an embodiment of this application;

[0036] Figure 6 This is a schematic diagram illustrating the fitting relationship between the comprehensive transport capacity evaluation parameters of oil source fractures and the apparent thickness of oil and gas reservoirs in a certain region, according to an embodiment of this application.

[0037] Figure 7 This is a schematic diagram of the structure of an evaluation system for the conduction capacity of an oil source fault, according to an embodiment of this application. Detailed Implementation

[0038] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0039] First, this invention provides a method 100 for evaluating the conductivity of oil-source faults, such as... Figure 1 As shown, the evaluation method 100 may include steps S110-S140.

[0040] Step S110: Determine the hydrocarbon expulsion intensity of the source rocks based on the source rock strata and organic matter characteristic parameters of the source rocks in the target study area.

[0041] The process can be referenced. Figure 2 Before determining the hydrocarbon expulsion intensity of source rocks, it is necessary to first identify the target study area and select sample points. The target study area is defined as a region characterized by fault-guided reservoir control. That is, areas with fault-guided reservoir control can be selected as the target study area, where faults primarily control the vertical migration of hydrocarbons, and sand bodies primarily control the lateral migration. Specifically, since hydrocarbon accumulation involves many factors, the main controlling factors for different hydrocarbon reservoirs are complex. In this invention, in addition to static geological elements such as source rocks, reservoirs, caprocks, and preservation conditions, the inventors have also considered that hydrocarbon accumulation is closely related to dynamic processes such as hydrocarbon generation and expulsion, migration and accumulation, and hydrocarbon preservation. This dynamic aspect does not refer to changes in specific values, but rather the matching of different processes. However, existing technologies do not consider the dynamic processes of hydrocarbon accumulation and neglect the ability of source rocks to generate or expel hydrocarbons and the process of hydrocarbon migration to the reservoir through faults, fractures, and other channels, evaluating only some currently available intuitive factors. In this regard, the present invention mainly focuses on the study of areas with fault-induced reservoir characteristics, which is more conducive to clarifying the relationship between various elements and the comprehensive transport capacity of faults.

[0042] In this embodiment of the application, the Wuyunting area (well area A) and the Baoyunting East area (well area B) of the Baochu slope zone in the Xihu Depression of the East China Sea shelf basin can be selected as the target study areas according to the above selection principles. For example... Figure 3 As shown, the Wuyunting and Baoyunting East areas have developed structural-lithological composite oil and gas reservoirs, with oil and gas mainly enriched in the Middle-Lower Eocene Pinghu Formation. The main source faults, F1 (Wubao Fault) and F2 (Baoshi Fault), are characterized by long extension lengths and large fault displacements. Analysis of the controlling factors of the existing reservoir traps along these two source faults suggests that both areas are controlled by near-depression oil and gas-conducting faults, with good fault-sand matching, thus enabling the formation of effective oil and gas transport systems. Furthermore, the later-stage faulting activity in these areas has had relatively weak destructive effects on the oil and gas reservoirs; therefore, fault conduction capacity is determined to be the main controlling factor for these reservoirs.

[0043] Next, it is necessary to determine the hydrocarbon generation and expulsion situation of the source rocks in the target study area during the main hydrocarbon accumulation period, including obtaining the main source rock strata and organic matter characteristic data of the main source rocks in the target study area, and then using these two data to draw a hydrocarbon expulsion intensity map of the main source rocks in the target study area.

[0044] In this application embodiment, geochemical methods confirm that the oil and gas in the Wuyunting area mainly originate from the Eocene Pinghu Formation source rocks. The oil source is complex, with different hydrocarbon accumulation models developed at different strata. Simultaneously, the upper and middle sections of the Pinghu Formation receive oil and gas supplies from the Santan Depression and Wuyunwa, while the lower section and Baoshi Formation mainly originate from the Wuyunwa. Moreover, current analysis suggests that the oil and gas in the eastern Baoyunting area primarily originate from the Pinghu Formation source rocks, indicating a dual-source hydrocarbon supply influenced by local source rocks, with the Santan Depression as the main source. Therefore, the Eocene Pinghu Formation source rocks can be considered the main source rocks in the target study area, and used as the research object. Furthermore, by reviewing data from the target study area, its hydrocarbon supply capacity during key hydrocarbon accumulation periods can be analyzed: the hydrocarbon generation intensity of the Pinghu Formation source rocks gradually increases from west to east, from the Baochu slope zone towards the Santan Depression, providing not only sufficient oil source conditions for fault conduction but also driving long-distance oil and gas migration.

[0045] In this embodiment, the hydrocarbon expulsion intensity of source rocks in the target study area can be determined using the organic matter characteristic parameters of the source rocks. These organic matter characteristic parameters may include: thickness of source rocks with different organic phases, organic matter abundance, and hydrogen index. In the application example, organic matter abundance / hydrogen index are obtained based on data from well sampling in the area, analyzed through geochemical experiments. For source rock thickness, there are two scenarios: in areas with existing wells, the thickness can be obtained from the actual thickness data revealed by drilling; in areas without wells, it is mainly predicted using geophysical methods based on seismic data and previous research results (including information from existing wells). Besides source rock thickness / organic matter abundance / hydrogen index, other parameters are generally those commonly used in the Xihu Depression. The formula for calculating the total hydrocarbon expulsion from source rocks can be expressed as:

[0046] Hydrocarbon emissions = A·H·(HI·Tr·GO-S·Ci)·TOC·ρ r / ρ g

[0047] Where: A—area of ​​source rock; H—thickness of source rock; ρ r —Rock density; ρ g —Natural gas density; HI—Hydrogen index of source rock; Tr—Conversion rate; G0—Gas generation rate (the proportion of gas generated to total hydrocarbons generated); TOC—Total organic carbon content; S—Initial kerogen adsorption capacity for oil and gas; Ci—Inert carbon content.

[0048] Then, for example, the aforementioned organic matter characteristic parameters can be input into Trinity software for hydrocarbon generation and expulsion simulation. Specifically, the Trinity oil and gas system analysis and exploration risk assessment software requires these parameters to be provided, then calculates and generates graphs, such as... Figure 4As shown, the hydrocarbon expulsion of the main source rock strata is calculated and a hydrocarbon expulsion intensity map is plotted. The hydrocarbon expulsion intensity E of the source rocks can then be read from the plotted hydrocarbon expulsion intensity map.

[0049] Furthermore, the inventors' research revealed that the vertical and lateral conductivity of oil-source faults jointly control the overall conductivity of oil-source faults, with the driving force of oil and gas transport and the degree of fault zone opening being important influencing factors. Since the overall conductivity of oil-source faults is affected by their oil and gas transport dynamics and the degree of fault zone opening, it cannot be quantitatively characterized by a single geological factor. Therefore, it is necessary to obtain multiple geological parameters of the target study area. In the embodiments of this application, the oil-source fault and reservoir geological parameters obtained in the target study area may specifically include: fault depth Z, fault displacement D, fault dip angle α, the angle β between the fault strike and the principal stress direction during the reservoir formation period, and the average density ρ of the overlying strata. r Formation water density ρ w , such as fault gouge ratio (SGR), fault growth index (Q), reservoir dip angle (θ), and reservoir thickness (h).

[0050] Therefore, the vertical transport capacity of the oil source fault can be determined by step S120 using the above-mentioned oil source fault and reservoir geological parameters, and the lateral transport capacity of the oil source fault can be determined by step S130.

[0051] Step S120: Determine the vertical transport capacity of the oil source fault based on the static rock pressure of the overlying strata in the target study area, the regional principal compressive stress components, and the lower limit of the pressure required for fault closure.

[0052] In the embodiments of this application, the pressure at the burial depth of the oil source fracture fault can be expressed as the sum of the static rock pressure N1 of the overlying strata and the regional principal compressive stress component N2.

[0053] Then, based on the static rock pressure N1 of the overlying strata in the target study area, the regional principal compressive stress component N2, and the lower limit of the pressure N required for fault closure, the following can be determined: min The vertical transport capacity F of the oil source fault is determined by the following formula. v :

[0054]

[0055] Among them, the static rock pressure of the overlying strata N1, the regional principal compressive stress component N2, and the lower limit of the pressure required for fault closure N min It can be determined by the following formula:

[0056] N1=Z(ρ r -ρ w )g cosα

[0057] N2=σsinαsinβ

[0058] N min =0.0012ρ w gZ

[0059] In the formula, Z is the burial depth of the cross-section, in meters; ρ r The average density of the overlying strata is given in g / cm³. 3 ;ρ w Density of formation water, g / cm³ 3 g is the acceleration due to gravity; σ is the horizontal principal compressive stress, MPa; α is the dip angle of the fault section, °; ​​β is the angle between the horizontal principal compressive stress and the fault strike, °.

[0060] Specifically, the inventors discovered that the driving force for oil and gas transport via fractures comes from both the residual pressure difference between the surrounding rock strata and the fracture zone, and the buoyancy of the oil and gas itself. Generally, for fractures in the same area of ​​an oil and gas basin or depression, the residual pressure difference can be considered nearly equal. Since the differences in the driving force for oil and gas transport across different fractures and different parts of the same fracture are mainly due to the difference in buoyancy caused by the different dip angles of the fracture face, the relative magnitude of the sine of the fracture dip angle can be used to represent the relative magnitude of the buoyancy: the larger the fracture dip angle, the stronger the driving force for oil and gas transport; conversely, the smaller the dip angle, the weaker the driving force. The greater the activity rate of the oil-source fracture, the stronger the fault activity, and the stronger the transport capacity. That is to say, referring to the above regarding the vertical transport capacity F... v The explanation is as follows: The larger the fault dip angle, the smaller the pressure exerted on the fault by the overlying strata. N1 = Z(ρ r -ρ w The smaller the value of cosα, the stronger the driving force for vertical migration of oil and gas, which is more conducive to vertical migration and transport of oil and gas.

[0061] Furthermore, during the activity of a fracture, the tectonic stress disrupts the formation of rock strata, forming fracture zones. These fracture zones contain numerous pores and fractures, which communicate with each other to form channels for oil and gas migration. The degree of fracture zone opening is primarily influenced by the angle between the direction of the regional principal compressive stress component and the fracture strike, as well as the magnitude of the pressure on the fracture surface: the smaller the angle between the fracture strike and the direction of the regional principal compressive stress component, the higher the degree of fracture zone opening; conversely, the larger the angle, the lower the degree. For dipping fractures, the degree of fracture zone opening is also affected by the magnitude of the normal pressure on the fault plane: the greater the normal pressure on the fault plane, the lower the degree of fracture zone opening; conversely, the lower the normal pressure, the higher the degree. This section also relates to the vertical transport capacity F. v The explanation corresponds to N2 = σsinαsinβ.

[0062] Step S130: Determine the lateral transport capacity of the oil source fault based on the contact length of the fault sand and the ratio of the fault gouge.

[0063] Specifically, the lateral transport capacity F of the oil-source fault can be determined using the following formula, based on the fault-sand contact length L and the fault gouge ratio SGR. l :

[0064] F l =L(1-SGR)

[0065] The contact length L of the fault sand and the ratio SGR of the fault gouge in the above formula can be determined by the following formula:

[0066]

[0067] In the formula, H i R represents the thickness of the i-th faulted layer, in meters. i denoted as , where is the mud content of the i-th layer displaced by the fault, in %; D is the vertical displacement of the fault, in m; h is the thickness of the sand body, in m; and θ is the dip angle of the sand body, in °.

[0068] Specifically, the more clay-filled material within the fault zone, the thicker the displaced strata and the higher the clay content smeared on the fault surface, the worse the fault zone opening, the greater the pressure required for hydrocarbon migration, and the less favorable the fault conduction. The corresponding SGR parameter is the lateral conduction capacity F. l The explanation is as follows. Mudstone has low porosity and permeability, and is often considered a source rock or caprock, lacking transport capacity. Sandstone, on the other hand, has relatively high porosity and permeability, and can serve as a reservoir or hydrocarbon migration channel. Therefore, the higher the mudstone infill and the higher the mudstone content coated on the cross-section, the greater the SGR (Sequencing Retention Rate), and the worse the corresponding lateral transport capacity.

[0069] It is evident that the coupling contact relationship and effective contact area between faults and sand bodies have a significant controlling effect on hydrocarbon accumulation. The contact area between sand bodies and effective migration faults (fault ridges) within the reservoir interval can relatively accurately reflect the fault-sand coupling migration of hydrocarbons; the larger the fault-sand contact area, the stronger the hydrocarbon migration capacity. This also reflects the lateral transport capacity F. l parameter.

[0070] Step S140: Based on the hydrocarbon expulsion intensity of the source rock, the vertical transport capacity of the oil source fault, the lateral transport capacity of the oil source fault, and the growth index of the oil source fault, determine the fault transport capacity evaluation parameters for evaluating the transport capacity of the oil source fault.

[0071] Specifically, it can be determined based on the hydrocarbon expulsion intensity E (dimension 10⁻⁶) of the source rock. 6 t / km 2 ), Vertical transport capacity F of oil source faults v Lateral transport capacity F of oil source faults lIn addition to the oil-source fault growth index Q (dimensionless), the following quantitative characterization model of fault conductivity is used to determine the fault conductivity evaluation parameter T:

[0072]

[0073] The oil source fault growth index Q can be determined using the following formula:

[0074]

[0075] In the formula, H1 is the thickness of the hanging wall of the fault, in meters; H2 is the thickness of the footwall of the fault, in meters.

[0076] The above formulas allow us to determine the parameters for evaluating fault conductivity. It should be noted that the combination of these four parameters is a key aspect of this invention. Existing technologies typically do not analyze vertical and lateral forces simultaneously, and rarely consider the hydrocarbon expulsion capacity of source rocks (which to some extent reflects the hydrocarbon injection dynamics). Furthermore, the application of these four parameters has shown good results in this region, thus demonstrating its technical value.

[0077] For example, in the embodiments of this application, the comprehensive transport capacity of the oil source faults F1 and F2 of the Wuyunting and Baoyunting East oil and gas reservoirs in the Baochu slope zone of the Xihu Depression in the East China Sea Basin can be calculated using a quantitative characterization model of fault transport capacity. The statistical table of each calculation parameter is shown in Table 1.

[0078] Table 1

[0079]

[0080] Through the above technical solutions, the evaluation method for the transmission capacity of oil-source faults proposed in this invention comprehensively considers multiple factors such as the hydrocarbon supply capacity of the main hydrocarbon source rocks during the main hydrocarbon accumulation period, the strength of fault activity, the driving force of oil and gas transmission, and the degree of opening of the fault zone. It quantitatively characterizes the comprehensive transmission capacity of oil-source faults and can be used to predict the transmission capacity of oil-source faults, which helps to find favorable areas and strata for future oil and gas exploration.

[0081] Furthermore, based on the quantitative characterization of fracture comprehensive conduction capacity, this invention can also fit the thickness of drilled oil and gas layers with fracture conduction capacity, which can predict the fracture conduction capacity of oil sources and help to find favorable areas and strata for future oil and gas exploration.

[0082] Specifically, after step S140, the evaluation method 100 of the present invention may further include:

[0083] Step S150: Verify the fault conduction capacity evaluation parameters based on the actual oil and gas layer thickness of the drilled well.

[0084] Specifically, the thickness of the oil and gas layer is based on actual drilling data. The higher the thickness, the better the oil and gas injection conditions received by this layer and this well, which proves that the transportation conditions are favorable and the transportation capacity is strong.

[0085] Based on the quantitative characterization of fault conductivity in the work area, step S140 yields the fault conductivity evaluation parameter T for each oil and gas field and each stratum. This parameter T can then be fitted with the actual oil and gas reservoir thickness from the drilling operation to verify the reliability of the evaluation parameter.

[0086] For example, see Figures 5a-5b These are oil and gas reservoir profiles of well A in Wuyunting area and well B in Baoyunting area, respectively. Figure 6 This is a graph showing the fitted relationship between the fault's comprehensive conductivity parameter T and the oil and gas reservoir thickness. From... Figure 6 The two show a strong positive correlation, indicating that the conductivity of oil-source faults controls the enrichment of oil and gas reservoirs, thus demonstrating the reliability of the fault conductivity evaluation and calculation method. Therefore, this invention can be used to predict the conductivity of oil-source faults, which will help in finding favorable areas and strata for future oil and gas exploration.

[0087] Device Examples

[0088] On the other hand, the present invention also provides an evaluation system 200 for the conductivity of oil-source faults, such as... Figure 7 As shown, the evaluation system 200 may include:

[0089] The first parameter determination device 210 determines the hydrocarbon expulsion intensity of the source rocks based on the source rock strata and organic matter characteristic parameters of the source rocks in the target study area. The target study area is an area with fault-guided reservoir characteristics.

[0090] The second parameter determination device 220 is used to determine the vertical transport capacity of the oil source fault based on the static rock pressure of the overlying strata in the target study area, the regional principal compressive stress component, and the lower limit of the pressure required for fault plane closure.

[0091] The third parameter determining device 230 is used to determine the lateral transport capacity of the oil-source fault based on the fault sand contact length and the fault gouge ratio; and

[0092] The evaluation parameter determination device 240 is used to determine the fault conduction capacity evaluation parameters for evaluating the conduction capacity of the oil source fault based on the hydrocarbon expulsion intensity of the source rock, the vertical conduction capacity of the oil source fault, the lateral conduction capacity of the oil source fault, and the growth index of the oil source fault.

[0093] Optionally, the organic matter characteristic parameters include: thickness of source rocks of different organic phases, organic matter abundance, and hydrogen index.

[0094] Optionally, the second parameter determining device 220 can be used to specifically perform the following: based on the static rock pressure B1 of the overlying strata in the target study area, the regional principal compressive stress component N2, and the lower limit of the pressure N required for fault closure. min The vertical transport capacity F of the oil source fault is determined by the following formula. v :

[0095]

[0096] Optionally, the overlying strata static rock pressure N1, the regional principal compressive stress component N2, and the lower limit of the pressure required for fault closure N1 are also considered. min The following formula is used to determine:

[0097] N1=Z(ρ r -ρ w )g cosα

[0098] N2=σsinαsinβ

[0099] N min =0.0012ρ w gZ

[0100] In the formula, Z is the burial depth of the cross section; ρ r ρ is the average density of the overlying strata. w σ is the density of formation water; g is the gravitational acceleration; σ is the horizontal principal compressive stress; α is the dip angle of the fault section; β is the angle between the horizontal principal compressive stress and the fault strike.

[0101] Optionally, the third parameter determining device 230 can be used to specifically perform the following: determining the lateral transport capacity F of the oil-source fault based on the sand contact length L and the fault gouge ratio SGR, using the following formula. l :

[0102] F l =L(1-SGR).

[0103] Optionally, the contact length L of the fault sand and the ratio SGR of the fault gouge are determined by the following formula:

[0104]

[0105] In the formula, H i R represents the thickness of the i-th layer that has been faulted; i denoted as , where is the mud content of the i-th layer displaced by the fault; D is the vertical displacement of the fault; h is the thickness of the sand body; and θ is the dip angle of the sand body.

[0106] Optionally, the evaluation parameter determination device 240 can be used for specific execution: based on the hydrocarbon expulsion intensity E of the source rock and the vertical transport capacity F of the oil source fault. v Lateral transport capacity F of oil source faults lAnd the oil-source fault growth index Q, the fault conductivity evaluation parameter T is determined by the following formula:

[0107]

[0108] In the formula, H1 is the thickness of the hanging wall of the fault; H2 is the thickness of the footwall of the fault.

[0109] Optionally, the evaluation system 200 may further include: a verification device for verifying the fault conductivity evaluation parameters based on the actual oil and gas reservoir thickness after determining the fault conductivity evaluation parameters.

[0110] Through the above technical solutions, this invention proposes a comprehensive approach to controlling fault conduction capacity, considering multiple factors such as the hydrocarbon supply capacity of the primary hydrocarbon source rocks during the main hydrocarbon accumulation period, the intensity of fault activity, the dynamics of oil and gas transport, and the degree of fault zone opening. This approach quantitatively characterizes the comprehensive conduction capacity of oil-source faults, which can be used to predict oil-source fault conduction capacity and helps in identifying favorable areas and strata for future oil and gas exploration. Furthermore, based on the quantitative characterization of comprehensive fault conduction capacity, this invention can also fit the thickness of drilled oil and gas layers with fault conduction capacity, enabling prediction of oil-source fault conduction capacity and further aiding in the identification of favorable areas and strata for future oil and gas exploration.

[0111] This invention also provides a storage medium storing a program that, when executed by a processor, implements a method for evaluating the transport capacity of an oil source fault.

[0112] This invention also provides a processor for running a program, wherein the program executes a method for evaluating the transport capacity of an oil-source fault.

[0113] This invention also provides a device, which may include a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it implements the various steps of the method for evaluating the transport capacity of the oil source fault described above. The device described herein may be a server, PC, PAD, mobile phone, etc.

[0114] This application also provides a computer program product that, when executed on a data processing device, is adapted to perform the various steps of an evaluation method for initializing the conduction capacity of an oil source fault as described above.

[0115] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0116] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0117] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0118] These computer program instructions may also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable device for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0119] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0120] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0121] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0122] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0123] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for evaluating the conductivity of an oil-source fault, characterized in that, The evaluation methods include: Based on the source rock strata of the target study area and the organic matter characteristic parameters of the source rocks, the hydrocarbon expulsion intensity of the source rocks is determined, wherein the target study area is an area with fault-guided reservoir characteristics; Based on the static rock pressure of the overlying strata in the target study area, the regional principal compressive stress components, and the lower limit of the pressure required for fault closure, the vertical transport capacity of the oil source fault is determined. The lateral transport capacity of the oil-source fault is determined based on the contact length of the fault sand and the fault gouge ratio; and Based on the hydrocarbon expulsion intensity of the source rock, the vertical transport capacity of the oil source fault, the lateral transport capacity of the oil source fault, and the growth index of the oil source fault, fault transport capacity evaluation parameters are determined to evaluate the transport capacity of the oil source fault.

2. The evaluation method according to claim 1, characterized in that, The organic matter characteristic parameters include: thickness of source rocks of different organic phases, organic matter abundance, and hydrogen index.

3. The evaluation method according to claim 1, characterized in that, The determination of the vertical transport capacity of the oil-source fault based on the static rock pressure of the overlying strata, the regional principal compressive stress components, and the lower limit of the pressure required for fault closure in the target study area includes: Based on the static rock pressure N1 of the overlying strata in the target study area, the regional principal compressive stress component N2, and the lower pressure limit N required for fault closure, ... min The vertical transport capacity F of the oil source fault is determined by the following formula. v :

4. The evaluation method according to claim 3, characterized in that, The static rock pressure N1 of the overlying strata, the principal compressive stress component N2 of the region, and the lower pressure limit N required for fault closure. min The following formula is used to determine: N1=Z(ρ r -r w )g thing N2=σsinαsinβ N min =0.0012ρ w gZ In the formula, Z is the burial depth of the cross section; ρ r ρ is the average density of the overlying strata. w denoted as ρ, where ρ is the density of formation water; g is the gravitational acceleration; σ is the horizontal principal compressive stress; α is the dip angle of the fault section; and β is the angle between the horizontal principal compressive stress and the fault strike.

5. The evaluation method according to claim 1, characterized in that, The determination of the lateral transport capacity of the oil-source fault based on the fault sand contact length and fault gouge ratio includes: Based on the contact length L of the fault sand and the fault gouge ratio SGR, the lateral transport capacity F of the oil-source fault is determined by the following formula. l : F l =L(1-SGR)。 6. The evaluation method according to claim 5, characterized in that, The contact length L of the fault sand and the ratio SGR of the fault gouge are determined by the following formulas: In the formula, H i R represents the thickness of the i-th layer that has been faulted; i denoted as , where is the mud content of the i-th layer displaced by the fault; D is the vertical displacement of the fault; h is the sand body thickness; and θ is the sand body dip angle.

7. The evaluation method according to claim 1, characterized in that, The fault conductivity evaluation parameters, determined based on the hydrocarbon expulsion intensity of the source rock, the vertical conductivity of the oil-source fault, the lateral conductivity of the oil-source fault, and the oil-source fault growth index, for evaluating the conductivity of the oil-source fault, include: Based on the hydrocarbon expulsion intensity E of the source rock and the vertical transport capacity F of the oil source fault... v The lateral transport capacity F of the oil source fault l And the oil-source fault growth index Q, the fault conductivity evaluation parameter T is determined by the following formula: In the formula, H1 is the thickness of the hanging wall of the fault; H2 is the thickness of the footwall of the fault.

8. The evaluation method according to claim 1, characterized in that, After determining the fault conduction capacity evaluation parameters, the evaluation method further includes: The fault conduction capacity evaluation parameters are verified based on the actual oil and gas layer thickness of the drilled well.

9. A system for evaluating the conductivity of an oil-source fault, characterized in that, The evaluation system includes: The first parameter determination device determines the hydrocarbon expulsion intensity of the source rock based on the source rock strata of the target study area and the organic matter characteristic parameters of the source rock, wherein the target study area is an area with fault-guided reservoir characteristics; The second parameter determination device is used to determine the vertical transport capacity of the oil source fault based on the static rock pressure of the overlying strata in the target study area, the regional principal compressive stress component, and the lower limit of the pressure required for fault closure. The third parameter determining device is used to determine the lateral transport capacity of the oil-source fault based on the fault sand contact length and the fault gouge ratio; and The evaluation parameter determination device is used to determine fault conductivity evaluation parameters for evaluating the conductivity of the oil source fault based on the hydrocarbon expulsion intensity of the source rock, the vertical conductivity of the oil source fault, the lateral conductivity of the oil source fault, and the growth index of the oil source fault.

10. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions for causing the machine to perform: a method for evaluating the transmissibility of an oil-source fault according to any one of claims 1-8.

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