A method for evaluating hydrocarbon source rock expulsion power

Abstract

The application provides a method for evaluating hydrocarbon source rock expulsion power. The method comprises: constructing a calculation model of each hydrocarbon source rock expulsion power; wherein the hydrocarbon source rock expulsion power comprises one or a combination of two or more of rock skeleton thermal expansion force, water thermal expansion force, oil thermal expansion force, gas thermal expansion force, compaction force, product volume increase force, clay mineral dehydration force and diffusion force; obtaining target layer parameters; based on the target layer parameters, using the calculation model of each hydrocarbon source rock expulsion power, determining the hydrocarbon source rock expulsion power of the target layer, thereby realizing the evaluation of the hydrocarbon source rock expulsion power of the target layer. The method provided by the application can quantitatively evaluate the rock skeleton thermal expansion force, water thermal expansion force, oil thermal expansion force, gas thermal expansion force, compaction force, product volume increase force, clay mineral dehydration force and / or diffusion force of the target layer, can be used for analyzing and determining the relative size of the expulsion power at different evolution stages, and can reliably realize the evaluation of the hydrocarbon source rock expulsion power.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas field development technology, and specifically relates to a method for evaluating the hydrocarbon expulsion dynamics of source rocks. Background Technology

[0002] Hydrocarbon expulsion from source rocks (i.e., the initial migration of oil and gas) is a highly complex geological issue. Because expulsion often occurs during migration processes in geological history, which are difficult to observe and reconstruct, current research on this issue largely relies on comprehensive analysis of geological data, scientific reasoning, and experimental results to propose theoretical understandings, many of which remain controversial. Current research on hydrocarbon expulsion from source rocks primarily focuses on the expulsion dynamics.

[0003] Extensive research has been conducted on the expulsion dynamics of hydrocarbon source rocks. Early studies focused on single dynamics. For example, at a certain burial depth, the fluid within the pores of a source rock is under hydrostatic pressure. When overlying strata are deposited again, the pressure increases, and the fluid within the pores inevitably bears a portion of this pressure, causing it to exceed the hydrostatic pressure and resulting in fluid expulsion. Some studies have shown that during rapid sediment settling, the expulsion of fluid from the source rock is obstructed, leading to abnormally high porosity and pressure. As pressure accumulates, when it exceeds the resistance, oil and gas are expelled. For instance, during the evolution of burial depth, the source rock framework and the oil, gas, and water within it expand with increasing temperature. Studies on water changes with temperature, pressure, and density have shown that if the formation is completely sealed and the pore space remains constant, the volume of water cannot increase with temperature, inevitably leading to increased internal pressure and prompting fluid expulsion. For example, some scholars have shown that when the surface of rock pores is hydrophilic, capillary force is the main driving force for the initial migration of hydrocarbons. Furthermore, some scholars believe that when tectonic movements occur in the strata, tectonic stress causes deformation of the rock skeleton, reducing the internal pore space. However, if the amount of fluid inside the rock does not decrease, this leads to an increase in internal fluid pressure, resulting in fluid expulsion. However, other scholars hold a different view. By analyzing the influence of tectonic stress on pore pressure, they have fitted a calculation model for the scale of hydrocarbon migration driven by tectonic stress. The results show that the distance of hydrocarbon migration driven by tectonic stress is negligible compared to the thickness of the source rock and cannot be used as the driving force for hydrocarbon expulsion from the source rock.

[0004] Besides analyzing single driving forces, some scholars have conducted comprehensive analyses of multiple forces. For example, some studies have shown that geological processes such as tectonic stress, thermal expansion, and organic matter thermal decomposition all alter fluid pressure, creating abnormal formation pressure, which is considered the primary driving force for oil and gas migration. Some scholars believe there are eight driving forces for primary oil and gas migration, including hydrocarbon generation pressurization, residual pressure from normal compaction, abnormally high pressure caused by undercompaction, tectonic stress, permeability forces caused by differences in salinity between source rocks and adjacent strata, diffusion forces caused by differences in internal fluid concentration, capillary forces, and buoyancy. Among these, hydrocarbon generation pressurization and capillary force differences are considered the most important driving forces for hydrocarbon expulsion during primary migration. Some scholars classify oil and gas migration forces into three types: intrasource migration, primary migration, and secondary migration. Migration related to source rock hydrocarbon expulsion is considered to be the first two types. Hydrogen generation pressurization and diffusion forces are considered the main hydrocarbon expulsion driving forces for intrasource migration in the formation of shale oil, coalbed methane, and other types of oil and gas.

[0005] However, current research on hydrocarbon expulsion dynamics from source rocks generally focuses on limited force coupling evaluations, resulting in poor reliability. How to reliably determine the hydrocarbon expulsion dynamics from source rocks is one of the urgent problems that needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a method and system that can reliably determine the hydrocarbon expulsion dynamics of source rocks.

[0007] To achieve the above objectives, the present invention provides a method for evaluating the hydrocarbon expulsion dynamics of source rocks, wherein the method includes:

[0008] Construct a calculation model for the hydrocarbon expulsion dynamics of each source rock; wherein, the hydrocarbon expulsion dynamics of the source rock include one or more of the following: thermal expansion force of the rock skeleton, hydrothermal expansion force, oil thermal expansion force, gas thermal expansion force, compressive force, product compressive force, clay mineral dehydration force, and diffusion force.

[0009] Obtain the target layer parameters;

[0010] Based on the parameters of the target layer, the hydrocarbon expulsion dynamics of each source rock in the target layer are determined by using the calculation model of the hydrocarbon expulsion dynamics of each source rock, thereby realizing the evaluation of the hydrocarbon expulsion dynamics of the source rocks in the target layer.

[0011] In the above method, preferably, the hydrocarbon expulsion power of the source rock includes the thermal expansion force of the rock skeleton, the hydrothermal expansion force, the oil thermal expansion force, the gas thermal expansion force, the compressive force, the product compressive force, the clay mineral dehydration force, and the diffusion force.

[0012] In the above method, preferably, the calculation model for the hydrocarbon expulsion dynamics of each source rock includes:

[0013] Identify the main factors controlling the hydrocarbon expulsion dynamics of each source rock, and construct a calculation model for the hydrocarbon expulsion dynamics of each source rock based on these main factors;

[0014] More preferably, the main factors controlling the hydrocarbon expulsion dynamics of each source rock include:

[0015] The effects of temperature, pressure, permeability, thermal expansion rate of rocks, porosity, density, discharge fluid volume, fluid viscosity, clay mineral content, and illite content of strata at different burial depths on the hydrocarbon discharge dynamics of each source rock were analyzed, and the main factors controlling the hydrocarbon discharge dynamics of each source rock were screened out.

[0016] In the above method, preferably, the calculation model of the thermal expansion force of the rock skeleton is a calculation model of the thermal expansion force of the rock skeleton with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged by the source rock due to the thermal expansion force of the rock skeleton, and the permeability of the source rock fluid.

[0017] More preferably, the calculation model for the thermal expansion force of the rock skeleton is:

[0018]

[0019] In the formula: f 岩 ΔQ is the thermal expansion force of the rock skeleton, in Pa. 岩 This refers to the amount of liquid discharged per unit volume of source rock due to thermal expansion of the rock skeleton, expressed in cubic meters. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 μ is the viscosity of the discharged fluid, in Pa·s; Z is the burial depth of the source rock, in meters; Δt is the time the force is applied, in seconds.

[0020] In the above method, preferably, the calculation model of hydrothermal expansion force is a calculation model of hydrothermal expansion force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to hydrothermal expansion force, and the permeability of the source rock fluid.

[0021] More preferably, the calculation model for the hydrothermal expansion force is:

[0022]

[0023] In the formula: f 水 ΔQ is the thermal expansion force of water, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 水 This refers to the amount of liquid discharged per unit volume of source rock due to hydrothermal expansion, expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2Z represents the burial depth of the source rock, in meters (m); Δt represents the time the force is applied, in seconds (s).

[0024] In the above method, preferably, the calculation model of oil thermal expansion force is a calculation model of oil thermal expansion force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to oil thermal expansion force, and the permeability of the source rock fluid.

[0025] More preferably, the calculation model for the thermal expansion force of the oil is:

[0026]

[0027] In the formula: f 油 ΔQ is the thermal expansion force of the oil, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 油 This refers to the amount of liquid discharged per unit volume of source rock due to the thermal expansion force of oil, expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time the force is applied, in seconds (s).

[0028] In the above method, preferably, the calculation model of gas thermal expansion force is a calculation model of gas thermal expansion force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to gas thermal expansion force, and the permeability of the source rock fluid.

[0029] More preferably, the calculation model for the gas thermal expansion force is:

[0030]

[0031] In the formula: f 气 ΔQ is the thermal expansion force of the gas, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 气 The volume of liquid discharged per unit volume of source rock due to gas thermal expansion force, expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time the force is applied, in seconds (s).

[0032] In the above method, preferably, the calculation model of pressure force is a calculation model of pressure force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to pressure force, and the permeability of the source rock fluid.

[0033] More preferably, the calculation model for the pressure force is:

[0034]

[0035] In the formula: f 压实力 Pressure is expressed in Pa; μ is the viscosity of the discharged fluid, expressed in Pa·s; ΔQ 压实力 This refers to the amount of liquid discharged per unit volume of source rock due to pressure, expressed in cubic meters (m³). 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time the force is applied, in seconds (s).

[0036] In the above method, preferably, the calculation model of the product compressibility force is a calculation model of the product compressibility force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to the product compressibility force, and the permeability of the source rock fluid.

[0037] More preferably, the calculation model for the product compatibilization capacity is as follows:

[0038]

[0039] In the formula: f 产物增容力 The product compatibilizing power is expressed in Pa; μ is the viscosity of the discharged fluid, expressed in Pa·s; ΔK W The derivative of the permeability of the source rock discharged fluid, in μm 2 ;ΔQ 生烃量 The fluid volume discharged per unit volume of source rock due to the compatibilizing force of the products (i.e., the amount of oil and gas generated from the source rock), expressed in m³. 3 Z represents the burial depth of the source rock, in meters (m); Δt represents the time the force is applied, in seconds (s).

[0040] In the above method, preferably, the calculation model of the clay mineral dehydration force is a calculation model of the clay mineral dehydration force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to the clay mineral dehydration force, and the permeability of the source rock fluid.

[0041] More preferably, the calculation model for the dehydration force of the clay mineral is as follows:

[0042]

[0043] In the formula: f 粘土矿物脱水力 ΔQ represents the dehydration force of clay minerals, expressed in Pa. 粘土矿物脱水力 The fluid volume discharged per unit volume of source rock due to the dehydration force of clay minerals (i.e., the amount of water released from montmorillonite per unit volume of source rock as burial depth increases), expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2μ is the viscosity of the discharged fluid, in Pa·s; Z is the burial depth of the source rock, in meters; Δt is the time the force is applied, in seconds.

[0044] In the above method, preferably, the calculation model of diffusion force is a calculation model of diffusion force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to diffusion force, and the permeability of the source rock fluid.

[0045] More preferably, the calculation model for the diffusion force is:

[0046]

[0047] In the formula: f 扩散力 ΔQ is the diffusion force, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 扩散相 This refers to the amount of fluid expelled per unit volume of source rock due to diffusion forces (i.e., the amount of hydrocarbons expelled by the diffusion phase), expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time the force is applied, in seconds (s).

[0048] In the above method, preferably, the hydrocarbon expulsion power from the source rock further includes oil-water capillary force; the calculation model for oil-water capillary force is as follows:

[0049]

[0050] In the formula: f 油水毛细管力 δ(O) represents the capillary force between oil and water (i.e., the difference in capillary force between oil and water), in Pa; δ(O) represents the interfacial tension at the oil-water interface, in N / m; θ w The wetting angle is r in degrees; r is the pore radius of the rock in degrees. -10 m.

[0051] In the above method, preferably, the hydrocarbon expulsion power from the source rock further includes gas-water capillary force:

[0052]

[0053] In the formula: f 气水毛细管力 δ(g) represents the capillary force between the gas and water (i.e., the difference in capillary force between gas and water), in Pa; δ(g) represents the interfacial tension at the gas-water interface, in N / m; θ w The wetting angle is r in degrees; r is the pore radius of the rock in degrees. -10 m.

[0054] In the above method, preferably, obtaining the target layer parameters includes:

[0055] Obtain the fluid volume discharged from the target layer source rock due to the thermal expansion force of the rock skeleton and / or the fluid volume discharged from the target layer source rock due to the hydrothermal expansion force and / or the fluid volume discharged from the target layer source rock due to the oil thermal expansion force and / or the fluid volume discharged from the target layer source rock due to the gas thermal expansion force and / or the fluid volume discharged from the target layer source rock due to the pressure force and / or the fluid volume discharged from the target layer source rock due to the product compatibilizing force and / or the fluid volume discharged from the target layer source rock due to the clay mineral dehydration force and / or the fluid volume discharged from the target layer source rock due to the diffusion force;

[0056] The viscosity of the fluid discharged from the target layer, the burial depth of the source rock in the target layer, the duration of the force applied to the target layer, and the fluid permeability of the source rock in the target layer are obtained.

[0057] More preferably, the acquisition of the fluid volume discharged by the target layer source rock due to the thermal expansion force of the rock skeleton and / or the fluid volume discharged by the target layer source rock due to the hydrothermal expansion force and / or the fluid volume discharged by the target layer source rock due to the oil thermal expansion force and / or the fluid volume discharged by the target layer source rock due to the gas thermal expansion force and / or the fluid volume discharged by the target layer source rock due to the pressure force and / or the fluid volume discharged by the target layer source rock due to the product compatibilizing force and / or the fluid volume discharged by the target layer source rock due to the clay mineral dehydration force and / or the fluid volume discharged by the target layer source rock due to the diffusion force includes:

[0058] Construct calculation models for the amount of fluid discharged from source rocks due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from source rocks due to the hydrothermal expansion force and / or the amount of fluid discharged from source rocks due to the oil thermal expansion force and / or the amount of fluid discharged from source rocks due to the gas thermal expansion force and / or the amount of fluid discharged from source rocks due to the pressure force and / or the amount of fluid discharged from source rocks due to the product compressibility force and / or the amount of fluid discharged from source rocks due to the clay mineral dehydration force and / or the amount of fluid discharged from source rocks due to the diffusion force.

[0059] Calculation models based on the amount of fluid discharged from source rocks due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from source rocks due to the hydrothermal expansion force and / or the amount of fluid discharged from source rocks due to the oil thermal expansion force and / or the amount of fluid discharged from source rocks due to the gas thermal expansion force and / or the amount of fluid discharged from source rocks due to the pressure force and / or the amount of fluid discharged from source rocks due to the product compressibility force and / or the amount of fluid discharged from source rocks due to the clay mineral dehydration force and / or the amount of fluid discharged from source rocks due to the diffusion force. The volumetric calculation model determines the amount of fluid discharged from the target layer source rock due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from the target layer source rock due to the hydrothermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the oil thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the gas thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the pressure force and / or the amount of fluid discharged from the target layer source rock due to the product compressibility force and / or the amount of fluid discharged from the target layer source rock due to the clay mineral dehydration force and / or the amount of fluid discharged from the target layer source rock due to the diffusion force.

[0060] More preferably, the calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of the rock skeleton is as follows:

[0061]

[0062] Where: ΔQ 岩 This refers to the amount of liquid discharged per unit volume of source rock due to thermal expansion of the rock skeleton, expressed in cubic meters. 3 ;△K sr (T) represents the relative change rate of the thermal expansion coefficient of rock with temperature, in %; The surface porosity of the source rock is expressed as a percentage. This refers to the volume occupied by the rock skeleton within a unit volume of source rock;

[0063] More preferably, the calculation model for the amount of fluid discharged from the source rock due to hydrothermal expansion force is as follows:

[0064]

[0065] Where: ΔQ 水 This refers to the amount of liquid discharged per unit volume of source rock due to hydrothermal expansion, expressed in m³. 3 S w Water saturation, in %; ΔK rw (T) represents the relative rate of change of the hydrothermal expansion coefficient with temperature, in %; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0066] More preferably, the calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of oil is as follows:

[0067]

[0068] Where: ΔQ 油 This refers to the amount of liquid discharged per unit volume of source rock due to the thermal expansion force of oil, expressed in m³. 3 S o Oil saturation, in %; ΔK ro (T) represents the relative rate of change of the thermal expansion coefficient of oil with temperature, in %; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0069] More preferably, the calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of gas is as follows:

[0070]

[0071] Where: ΔQ 气 The volume of liquid discharged per unit volume of source rock due to gas thermal expansion force, expressed in m³. 3 S g Gas saturation, in %; ΔK rg (P,T) is the gas volume restitution coefficient, with dimensionless units; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0072] More preferably, the calculation model for the amount of fluid discharged from the source rock due to pressure is as follows:

[0073]

[0074] Where: ΔQ 压实力 This refers to the amount of liquid discharged per unit volume of source rock due to pressure, expressed in cubic meters (m³). 3 ; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0075] More preferably, the calculation model for the amount of fluid discharged from the source rock due to the compatibilizing force of the products is as follows:

[0076]

[0077] Where: ΔQ 生烃量 The fluid volume discharged per unit volume of source rock due to the compatibilizing force of the products (i.e., the amount of oil and gas generated from the source rock), expressed in m³. 3 ρ represents the density of the source rock, in kg / m³. 3 ΔTOC represents the amount of organic carbon generated per unit mass of source rock during hydrocarbon generation and conversion reactions in geological history, expressed as a percentage (%). a Oil and gas generation rate, in meters (m³) 3 / t;

[0078] More preferably, the calculation model for the amount of fluid discharged from the source rock due to the dehydration force of clay minerals is as follows:

[0079] ΔQ 粘土矿物脱水力 =0.245·P c ·P m ·ρ

[0080] Where: ΔQ 粘土矿物脱水力 The fluid volume discharged per unit volume of source rock due to the dehydration force of clay minerals (i.e., the amount of water released from montmorillonite per unit volume of source rock as burial depth increases), expressed in m³. 3 ;P c The content of clay minerals per unit volume of source rock, in %; P m ρ represents the content of montmorillonite, which undergoes transformation and dehydration in clay minerals, in %; ρ is the density of the source rock, in kg / m³. 3 ;

[0081] More preferably, the calculation model for the amount of fluid discharged from the source rock due to diffusion force is as follows:

[0082]

[0083] Where: ΔQ 扩散相 This refers to the amount of fluid expelled per unit volume of source rock due to diffusion forces (i.e., the amount of hydrocarbons expelled by the diffusion phase), expressed in m³. 3 w represents the concentration gradient of oil and gas, in units of (m³). 3 / m 3 D is the diffusion coefficient of natural gas in underground rock, in meters (m³). 2 / s; S is the area of ​​the source rock where diffusion occurred, in m². 2 Δt is the time during which the force is applied, in seconds.

[0084] The technical solution provided by this invention can quantitatively evaluate the thermal expansion force, hydrothermal expansion force, oil thermal expansion force, gas thermal expansion force, compressive strength, product compressive strength, clay mineral dehydration force and / or diffusion force of the target rock skeleton. It can be used to analyze and determine the relative magnitude of the hydrocarbon expulsion dynamics that lead to the amount of hydrocarbons expelled from the source rock at different evolution stages, and reliably evaluate the hydrocarbon expulsion dynamics of the source rock. Attached Figure Description

[0085] Figure 1 This is a flowchart of a method for evaluating the hydrocarbon expulsion dynamics of source rocks, provided in an embodiment of the present invention.

[0086] Figure 2 This is a diagram showing the amount of fluid discharged from the source rock at different burial depths of the target layer in Embodiment 1 of the present invention due to various hydrocarbon expulsion forces.

[0087] Figure 3 This is a diagram showing the cumulative fluid volume discharged from source rocks at different burial depths within the target layer in Embodiment 1 of the present invention due to various hydrocarbon expulsion forces.

[0088] Figure 4 This is a graph showing the trend of hydrocarbon expulsion power in each target layer with burial depth in Embodiment 1 of the present invention. Detailed Implementation

[0089] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0090] See Figure 1 A specific embodiment of the present invention provides a method for evaluating the hydrocarbon expulsion dynamics of source rocks, wherein the method includes:

[0091] Step S1: Construct a calculation model for the hydrocarbon expulsion dynamics of each source rock; wherein, the hydrocarbon expulsion dynamics of the source rock include one or more of the following: thermal expansion force of the rock skeleton, hydrothermal expansion force, oil thermal expansion force, gas thermal expansion force, compressive force, product compressive force, clay mineral dehydration force, and diffusion force.

[0092] Step S2: Obtain the target layer parameters;

[0093] Step S3: Based on the parameters of the target layer, use the calculation model of the hydrocarbon expulsion dynamics of each source rock to determine the hydrocarbon expulsion dynamics of each source rock in the target layer, thereby realizing the evaluation of the hydrocarbon expulsion dynamics of the source rocks in the target layer.

[0094] Furthermore, the hydrocarbon expulsion force of the source rock includes the thermal expansion force of the rock skeleton, the hydrothermal expansion force, the oil thermal expansion force, the gas thermal expansion force, the compressive force, the product compressive force, the clay mineral dehydration force, and the diffusion force.

[0095] In another location, step S1 includes:

[0096] Identify the main factors controlling the hydrocarbon expulsion dynamics of each source rock, and construct a calculation model for the hydrocarbon expulsion dynamics of each source rock based on these main factors;

[0097] Furthermore, the main factors controlling the hydrocarbon expulsion dynamics of each source rock were identified as follows:

[0098] The effects of temperature, pressure, permeability, thermal expansion rate of rocks, porosity, density, discharge fluid volume, fluid viscosity, clay mineral content, and illite content of strata at different burial depths on the hydrocarbon discharge dynamics of each source rock were analyzed, and the main factors controlling the hydrocarbon discharge dynamics of each source rock were screened out.

[0099] Furthermore, the calculation model for the thermal expansion force of the rock skeleton is a calculation model for the thermal expansion force of the rock skeleton with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged by the source rock due to the thermal expansion force of the rock skeleton, and the permeability of the source rock fluid.

[0100] Furthermore, the calculation model for the thermal expansion force of the rock skeleton is as follows:

[0101]

[0102] In the formula: f 岩 ΔQ is the thermal expansion force of the rock skeleton (i.e., the thermal expansion force of the rock skeleton at burial depth Z), in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 岩 The volume of liquid discharged per unit volume of source rock due to thermal expansion of the rock skeleton (i.e., the volume of liquid discharged per unit volume of source rock at burial depth Z due to thermal expansion of the rock skeleton), in meters. 3 ;△K W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0103] Furthermore, the calculation model for hydrothermal expansion force is a calculation model for hydrothermal expansion force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to hydrothermal expansion force, and the permeability of the source rock fluid.

[0104] Furthermore, the calculation model for the hydrothermal expansion force is as follows:

[0105]

[0106] In the formula: f 水ΔQ is the thermal expansion force of water (i.e., the thermal expansion force of water at burial depth Z), in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 水 The volume of liquid discharged per unit volume of source rock due to hydrothermal expansion force (i.e., the volume of liquid discharged per unit volume of source rock at burial depth Z due to hydrothermal expansion force), in meters. 3 ;△K W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0107] Furthermore, the calculation model for the thermal expansion force of oil is a calculation model for the thermal expansion force of oil with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to the thermal expansion force of oil, and the permeability of the source rock fluid.

[0108] Furthermore, the calculation model for the thermal expansion force of the oil is as follows:

[0109]

[0110] In the formula: f 油 ΔQ is the thermal expansion force of the oil (i.e., the thermal expansion force of the oil at burial depth Z), in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 油 The volume of liquid discharged per unit volume of source rock due to thermal expansion force of oil (i.e., the volume of liquid discharged per unit volume of source rock at burial depth Z due to thermal expansion force of oil), in meters. 3 ;△K W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0111] Furthermore, the calculation model for gas thermal expansion force is a calculation model for gas thermal expansion force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to gas thermal expansion force, and the permeability of the source rock fluid.

[0112] Furthermore, the calculation model for the thermal expansion force of the gas is as follows:

[0113]

[0114] In the formula: f 气 ΔQ is the thermal expansion force of the gas (i.e., the thermal expansion force of the gas at burial depth Z), in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 气 The volume of liquid discharged per unit volume of source rock due to thermal expansion force (i.e., the volume of liquid discharged per unit volume of source rock at burial depth Z due to thermal expansion force), in meters. 3 ;△K W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0115] Furthermore, the calculation model for pressure force is a calculation model that considers the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to pressure force, and the permeability of the source rock fluid.

[0116] Furthermore, the calculation model for the pressure force is as follows:

[0117]

[0118] In the formula: f 压实力 The pressure is expressed as pressure at depth Z (Pa); μ is the viscosity of the discharged fluid (Pa·s); ΔQ 压实力 This represents the amount of liquid discharged per unit volume of source rock due to pressure (i.e., the amount of liquid discharged per unit volume of source rock at burial depth Z due to pressure), expressed in m³. 3 ;△K W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0119] Furthermore, the calculation model for product compressibility is a calculation model for product compressibility with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to product compressibility, and the permeability of the source rock fluid.

[0120] Furthermore, the calculation model for the product's compatibilizing power is as follows:

[0121]

[0122] In the formula: f 产物增容力 The product compatibilizing force (i.e., the product compatibilizing force at burial depth Z) is expressed in Pa; μ is the viscosity of the discharged fluid, expressed in Pa·s; ΔK W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 ;ΔQ 生烃量 This refers to the amount of fluid discharged per unit volume of source rock due to the compatibilizing force of the products (i.e., the amount of fluid discharged per unit volume of source rock at burial depth Z due to the compatibilizing force of the products, which is the amount of oil and gas generated by the source rock), expressed in m³. 3 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0123] Furthermore, the calculation model for the dehydration force of clay minerals is a calculation model for the dehydration force of clay minerals in relation to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to the dehydration force of clay minerals, and the permeability of the source rock fluid.

[0124] Furthermore, the calculation model for the dehydration capacity of the clay minerals is as follows:

[0125]

[0126] In the formula: f 粘土矿物脱水力 ΔQ is the clay mineral dehydration force (i.e., the clay mineral dehydration force at burial depth Z), in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 粘土矿物脱水力 The fluid volume discharged per unit volume of source rock due to the dehydration force of clay minerals (i.e., the fluid volume discharged per unit volume of source rock at burial depth Z due to the dehydration force of clay minerals, i.e., the amount of water released by montmorillonite as burial depth increases), in m³. 3 ;△K W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0127] Furthermore, the calculation model for diffusion force is a calculation model for diffusion force with respect to the viscosity of the discharged fluid, the burial depth of the source rock, the time of force application, the amount of fluid discharged from the source rock due to diffusion force, and the permeability of the source rock fluid.

[0128] Furthermore, the calculation model for the diffusion force is as follows:

[0129]

[0130] In the formula: f 扩散力 ΔQ is the diffusion force (i.e., the diffusion force at burial depth Z), in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 扩散相 This refers to the amount of fluid expelled per unit volume of source rock due to diffusion forces (i.e., the amount of fluid expelled per unit volume of source rock at burial depth Z due to diffusion forces; the amount of fluid expelled due to diffusion forces is the amount of hydrocarbons expelled by the diffusion phase), expressed in m³. 3 ;△K W The derivative of the permeability of the source rock expelled fluid (the permeability of the source rock expelled fluid varies at different burial depths; the derivative of the permeability of the source rock expelled fluid is the change in permeability of the source rock expelled fluid at burial depth Z), μm 2 Z represents the burial depth of the source rock, in meters; Δt represents the time of force application (i.e., the time required for the source rock to burial from its initial depth to its current depth), in seconds.

[0131] Furthermore, the hydrocarbon expulsion dynamics from source rocks further include oil-water capillary forces; the calculation model for oil-water capillary forces is as follows:

[0132]

[0133] In the formula: f 油水毛细管力 δ(O) represents the capillary force between oil and water (i.e., the difference in capillary force between oil and water), in Pa; δ(O) represents the interfacial tension at the oil-water interface, in N / m; θ w The wetting angle is r in degrees; r is the pore radius of the rock in degrees. -10 m.

[0134] Furthermore, the hydrocarbon expulsion power of the source rock further includes gas-water capillary force:

[0135]

[0136] In the formula: f 气水毛细管力 δ(g) represents the capillary force between the gas and water (i.e., the difference in capillary force between gas and water), in Pa; δ(g) represents the interfacial tension at the gas-water interface, in N / m; θ w The wetting angle is r in degrees; r is the pore radius of the rock in degrees. -10 m.

[0137] In another location, step S2 includes:

[0138] Step S21: Obtain the viscosity of the fluid discharged from the target layer, the burial depth of the source rock in the target layer, the time of force action in the target layer, and the fluid permeability of the source rock in the target layer;

[0139] Step S22: Obtain the amount of fluid discharged from the target layer source rock due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from the target layer source rock due to the hydrothermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the oil thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the gas thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the pressure force and / or the amount of fluid discharged from the target layer source rock due to the product compatibilizing force and / or the amount of fluid discharged from the target layer source rock due to the clay mineral dehydration force and / or the amount of fluid discharged from the target layer source rock due to the diffusion force;

[0140] Furthermore, step S22 includes:

[0141] Construct calculation models for the amount of fluid discharged from source rocks due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from source rocks due to the hydrothermal expansion force and / or the amount of fluid discharged from source rocks due to the oil thermal expansion force and / or the amount of fluid discharged from source rocks due to the gas thermal expansion force and / or the amount of fluid discharged from source rocks due to the pressure force and / or the amount of fluid discharged from source rocks due to the product compressibility force and / or the amount of fluid discharged from source rocks due to the clay mineral dehydration force and / or the amount of fluid discharged from source rocks due to the diffusion force.

[0142] Calculation models based on the amount of fluid discharged from source rocks due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from source rocks due to the hydrothermal expansion force and / or the amount of fluid discharged from source rocks due to the oil thermal expansion force and / or the amount of fluid discharged from source rocks due to the gas thermal expansion force and / or the amount of fluid discharged from source rocks due to the pressure force and / or the amount of fluid discharged from source rocks due to the product compressibility force and / or the amount of fluid discharged from source rocks due to the clay mineral dehydration force and / or the amount of fluid discharged from source rocks due to the diffusion force. The volumetric calculation model determines the amount of fluid discharged from the target layer source rock due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from the target layer source rock due to the hydrothermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the oil thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the gas thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the pressure force and / or the amount of fluid discharged from the target layer source rock due to the product compressibility force and / or the amount of fluid discharged from the target layer source rock due to the clay mineral dehydration force and / or the amount of fluid discharged from the target layer source rock due to the diffusion force.

[0143] Further along, the calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of the rock skeleton is as follows:

[0144]

[0145] Where: ΔQ 岩 This refers to the amount of liquid discharged per unit volume of source rock due to thermal expansion of the rock skeleton, expressed in cubic meters. 3 ;△K sr (T) represents the relative change rate of the thermal expansion coefficient of rock with temperature, in %; The surface porosity of the source rock is expressed as a percentage. This refers to the volume occupied by the rock skeleton within a unit volume of source rock;

[0146] Further along, the calculation model for the amount of fluid discharged from the source rock due to hydrothermal expansion is as follows:

[0147]

[0148] Where: ΔQ 水 This refers to the amount of liquid discharged per unit volume of source rock due to hydrothermal expansion, expressed in m³. 3 S w Water saturation, in %; ΔK rw (T) represents the relative rate of change of the hydrothermal expansion coefficient with temperature, in %; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0149] Further along, the calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of oil is as follows:

[0150]

[0151] Where: ΔQ 油 This refers to the amount of liquid discharged per unit volume of source rock due to the thermal expansion force of oil, expressed in m³. 3 S o Oil saturation, in %; ΔK ro (T) represents the relative rate of change of the thermal expansion coefficient of oil with temperature, in %; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0152] Further along, the calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of gas is as follows:

[0153]

[0154] Where: ΔQ 气 The volume of liquid discharged per unit volume of source rock due to gas thermal expansion force, expressed in m³. 3 S g Gas saturation, in %; ΔK rg (P,T) is the gas volume restitution coefficient, with dimensionless units; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0155] In another location, the calculation model for the amount of fluid discharged from the source rock due to pressure is as follows:

[0156]

[0157] Where: ΔQ 压实力 This refers to the amount of liquid discharged per unit volume of source rock due to pressure, expressed in cubic meters (m³). 3 ; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0158] In another location, the calculation model for the amount of fluid discharged from the source rock due to the compatibilizing force of the products is as follows:

[0159]

[0160] Where: ΔQ 生烃量 The fluid volume discharged per unit volume of source rock due to the compatibilizing force of the products (i.e., the amount of oil and gas generated from the source rock), expressed in m³. 3 π represents the density of the source rock, in kg / m³. 3 ΔTOC represents the amount of organic carbon generated per unit mass of source rock during hydrocarbon generation and conversion reactions in geological history, expressed as a percentage (%). a Oil and gas generation rate, in meters (m³) 3 / t;

[0161] In another location, the calculation model for the amount of fluid discharged from the source rock due to the dehydration force of clay minerals is as follows:

[0162] ΔQ 粘土矿物脱水力 =0.245·P c ·P m ·ρ

[0163] Where: ΔQ 粘土矿物脱水力The fluid volume discharged per unit volume of source rock due to the dehydration force of clay minerals (i.e., the amount of water released from montmorillonite per unit volume of source rock as burial depth increases), expressed in m³. 3 ;P c The content of clay minerals per unit volume of source rock, in %; P m ρ represents the content of montmorillonite, which undergoes transformation and dehydration in clay minerals, in %; ρ is the density of the source rock, in kg / m³. 3 ;

[0164] Further along, the calculation model for the amount of fluid discharged from the source rock due to diffusion force is as follows:

[0165]

[0166] Where: ΔQ 扩散相 This refers to the amount of fluid expelled per unit volume of source rock due to diffusion forces (i.e., the amount of hydrocarbons expelled by the diffusion phase), expressed in m³. 3 w represents the concentration gradient of oil and gas, in m³. 3 / m 3 / m; D is the diffusion coefficient of natural gas in underground rock, in meters. 2 / s; S is the area of ​​the source rock where diffusion occurred, in m². 2 Δt is the time during which the force acts (i.e., the time required for the source rock to increase from its initial burial depth of Z1 to its current burial depth of Z2), in seconds.

[0167] Example 1

[0168] Taking the hydrocarbon expulsion dynamics evaluation of Upper Ordovician carbonate source rocks in a certain region as an example, this invention illustrates the hydrocarbon expulsion dynamics evaluation method for source rocks; the specific steps are as follows:

[0169] 1. Construct calculation models for the thermal expansion force, hydrothermal expansion force, oil thermal expansion force, gas thermal expansion force, compressive force, product compressive force, clay mineral dehydration force, diffusion force, oil-water capillary force, and gas-water capillary force of the rock skeleton;

[0170] Specifically: The calculation model for the thermal expansion force of the rock skeleton is as follows:

[0171]

[0172] In the formula: f 岩 ΔQ is the thermal expansion force of the rock skeleton, in Pa. 岩 This refers to the amount of liquid discharged per unit volume of source rock due to thermal expansion of the rock skeleton, expressed in cubic meters. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2μ is the viscosity of the discharged fluid, in Pa·s; Z is the burial depth of the source rock, in meters; Δt is the time the force is applied, in seconds.

[0173] The calculation model for hydrothermal expansion force is as follows:

[0174]

[0175] In the formula: f 水 ΔQ is the thermal expansion force of water, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 水 This refers to the amount of liquid discharged per unit volume of source rock due to hydrothermal expansion, expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time during which the force is applied, in seconds (s).

[0176] The calculation model for the thermal expansion force of oil is as follows:

[0177]

[0178] In the formula: f 油 ΔQ is the thermal expansion force of the oil, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 油 This refers to the amount of liquid discharged per unit volume of source rock due to the thermal expansion force of oil, expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time during which the force is applied, in seconds (s).

[0179] The calculation model for thermal expansion force of air is as follows:

[0180]

[0181] In the formula: f 气 ΔQ is the thermal expansion force of the gas, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 气 The volume of liquid discharged per unit volume of source rock due to gas thermal expansion force, expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time during which the force is applied, in seconds (s).

[0182] The calculation model for pressure force is as follows:

[0183]

[0184] In the formula: f 压实力Pressure is expressed in Pa; μ is the viscosity of the discharged fluid, expressed in Pa·s; ΔK W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time of force application, in seconds (s).

[0185] The calculation model for product compatibilization capacity is as follows:

[0186]

[0187] In the formula: f 产物增容力 The product compatibilizing power is expressed in Pa; μ is the viscosity of the discharged fluid, expressed in Pa·s; ΔK W The derivative of the permeability of the source rock discharged fluid, in μm 2 ;ΔQ 生烃量 The fluid volume discharged per unit volume of source rock due to the compatibilizing force of the products (i.e., the amount of oil and gas generated from the source rock), expressed in m³. 3 Z represents the burial depth of the source rock, in meters (m); Δt represents the time during which the force is applied, in seconds (s).

[0188] The calculation model for the dehydration force of clay minerals is as follows:

[0189]

[0190] In the formula: f 粘土矿物脱水力 ΔQ is the dehydration force of clay minerals, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 粘土矿物脱水力 The fluid volume discharged per unit volume of source rock due to the dehydration force of clay minerals (i.e., the amount of water released from montmorillonite per unit volume of source rock as burial depth increases), expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time during which the force is applied, in seconds (s).

[0191] The calculation model for diffusion force is as follows:

[0192]

[0193] In the formula: f 扩散力 ΔQ is the diffusion force, in Pa; μ is the viscosity of the discharged fluid, in Pa·s; ΔQ 扩散相 This refers to the amount of fluid expelled per unit volume of source rock due to diffusion forces (i.e., the amount of hydrocarbons expelled by the diffusion phase), expressed in m³. 3 ;△K W The derivative of the permeability of the source rock discharged fluid, in μm 2 Z represents the burial depth of the source rock, in meters (m); Δt represents the time the force is applied, in seconds (s).

[0194] The calculation model for capillary force in oil and water is as follows:

[0195]

[0196] In the formula: f 油水毛细管力 δ(O) represents the capillary force between oil and water (i.e., the difference in capillary force between oil and water), in Pa; δ(O) represents the interfacial tension at the oil-water interface, in N / m; θ w The wetting angle is r in degrees; r is the pore radius of the rock in degrees. -10 m;

[0197] Hydrocarbon expulsion from source rocks further includes gas-water capillary forces:

[0198]

[0199] In the formula: f 气水毛细管力 δ(g) represents the capillary force between the gas and water (i.e., the difference in capillary force between gas and water), in Pa; δ(g) represents the interfacial tension at the gas-water interface, in N / m; θ w The wetting angle is r in degrees; r is the pore radius of the rock in degrees. -10 m.

[0200] 2. Obtain parameters at different burial depths of the target layer;

[0201] Specifically: obtain the viscosity of the fluid discharged from the target layer, the burial depth of the source rock in the target layer, the time of force application at different burial depths of the target layer, the fluid permeability of the source rock at different burial depths of the target layer, the interfacial tension of the gas-water interface at different burial depths of the target layer, the interfacial tension of the oil-water interface at different burial depths of the target layer, the wetting angle at different burial depths of the target layer, and the pore radius of the rock at different burial depths of the target layer.

[0202] This study constructs calculation models for the amount of fluid expelled from source rocks due to the thermal expansion force of the rock skeleton, the hydrothermal expansion force, the oil thermal expansion force, the gas thermal expansion force, the pressure force, the product compatibilization force, the clay mineral dehydration force, and the diffusion force. Based on these models, calculations are performed on the fluid expelled from source rocks due to the thermal expansion force of the rock skeleton, the hydrothermal expansion force, the oil thermal expansion force, the gas thermal expansion force, and the pressure force. The calculation models for the amount of fluid discharged from source rocks due to the compressive force of products, the dehydration force of clay minerals, and the diffusion force are used to determine the amount of fluid discharged from source rocks at different burial depths in the target layer due to the thermal expansion force of the rock skeleton, the hydrothermal expansion force, the oil thermal expansion force, the gas thermal expansion force, the pressure force, the compressive force of products, the dehydration force of clay minerals, and the diffusion force.

[0203] The calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of the rock skeleton is as follows:

[0204]

[0205] Where: ΔQ 岩 This refers to the amount of liquid discharged per unit volume of source rock due to thermal expansion of the rock skeleton, expressed in cubic meters. 3 ;△K sr (T) represents the relative change rate of the thermal expansion coefficient of rock with temperature, in %; The surface porosity of the source rock is expressed as a percentage. This refers to the volume occupied by the rock skeleton within a unit volume of source rock;

[0206] The calculation model for the amount of fluid discharged from the source rock due to hydrothermal expansion is as follows:

[0207]

[0208] Where: ΔQ 水This refers to the amount of liquid discharged per unit volume of source rock due to hydrothermal expansion, expressed in m³. 3 S w Water saturation, in %; ΔK rw (T) represents the relative rate of change of the hydrothermal expansion coefficient with temperature, in %; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0209] The calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of oil is as follows:

[0210]

[0211] Where: ΔQ 油 This refers to the amount of liquid discharged per unit volume of source rock due to the thermal expansion force of oil, expressed in m³. 3 S o Oil saturation, in %; ΔK ro (T) represents the relative rate of change of the thermal expansion coefficient of oil with temperature, in %; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0212] The calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of gas is as follows:

[0213]

[0214] Where: ΔQ 气 The volume of liquid discharged per unit volume of source rock due to gas thermal expansion force, expressed in m³. 3 S g Gas saturation, in %; ΔK rg (P,T) is the gas volume restitution coefficient, with dimensionless units; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0215] The calculation model for the amount of fluid discharged from source rocks due to pressure is as follows:

[0216]

[0217] Where: ΔQ 压实力 This refers to the amount of liquid discharged per unit volume of source rock due to pressure, expressed in cubic meters (m³). 3 ; The surface porosity of hydrocarbon source rocks is expressed as a percentage (%). The original porosity of the source rock is expressed as a percentage (%). The current porosity of the source rock is expressed as a percentage (%).

[0218] The calculation model for the amount of fluid discharged from the source rock due to the compatibilizing force of the products is as follows:

[0219]

[0220] Where: ΔQ 生烃量 The fluid volume discharged per unit volume of source rock due to the compatibilizing force of the products (i.e., the amount of oil and gas generated from the source rock), expressed in m³. 3 ρ represents the density of the source rock, in kg / m³. 3 ΔTOC represents the amount of organic carbon generated per unit mass of source rock during hydrocarbon generation and conversion reactions in geological history, expressed as a percentage (%). a Oil and gas generation rate, in meters (m³) 3 / t;

[0221] The calculation model for the amount of fluid discharged from the source rock due to the dehydration force of clay minerals is as follows:

[0222] ΔQ 粘土矿物脱水力 =0.245·P c ·P m ·ρ

[0223] Where: ΔQ 粘土矿物脱水力 The fluid volume discharged per unit volume of source rock due to the dehydration force of clay minerals (i.e., the amount of water released from montmorillonite per unit volume of source rock as burial depth increases), expressed in m³. 3 ;P c The content of clay minerals per unit volume of source rock, in %; P m ρ represents the content of montmorillonite, which undergoes transformation and dehydration in clay minerals, in %; ρ is the density of the source rock, in kg / m³. 3 ;

[0224] The calculation model for the amount of fluid discharged from the source rock due to diffusion force is as follows:

[0225]

[0226] Where: ΔQ 扩散相 This refers to the amount of fluid expelled per unit volume of source rock due to diffusion forces (i.e., the amount of hydrocarbons expelled by the diffusion phase), expressed in m³. 3 w represents the concentration gradient of oil and gas, in m³. 3 / m 3 / m; D is the diffusion coefficient of natural gas in underground rock, in meters. 2 / s; S is the area of ​​the source rock where diffusion occurred, in m². 2Δt is the time during which the force acts, in seconds.

[0227] The fluid volumes discharged from source rocks at different burial depths in the target layer due to thermal expansion forces (i.e., the sum of fluid volumes discharged due to thermal expansion forces of the rock skeleton, hydrothermal expansion forces, oil thermal expansion forces, and gas thermal expansion forces), fluid volumes discharged due to thermal expansion forces of the rock skeleton, fluid volumes discharged due to pressure forces, fluid volumes discharged due to product compatibilizing forces, fluid volumes discharged due to clay mineral dehydration forces, and fluid volumes discharged due to diffusion forces are as follows: Figure 2 As shown, the fluid volumes discharged from source rocks at different burial depths within the target layer due to the cumulative effects of thermal expansion (i.e., the sum of fluid volumes discharged due to the cumulative effects of thermal expansion forces of the rock skeleton, hydrothermal expansion, oil thermal expansion, and gas thermal expansion), pressure, product compatibilization forces, clay mineral dehydration forces, and diffusion forces are as follows: Figure 3 As shown.

[0228] 3. Based on parameters at different burial depths of the target layer, using calculation models of thermal expansion force, hydrothermal expansion force, oil thermal expansion force, gas thermal expansion force, compressive strength, product compressive strength, clay mineral dehydration force, diffusion force, oil-water capillary force, and gas-water capillary force of the rock skeleton at different burial depths, determine the thermal expansion force, hydrothermal expansion force, oil thermal expansion force, gas thermal expansion force, compressive strength, product compressive strength, clay mineral dehydration force, diffusion force, oil-water capillary force, and gas-water capillary force of the rock skeleton at different burial depths of the target layer;

[0229] The results are as follows Figure 4 As shown.

[0230] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for evaluating the hydrocarbon expulsion dynamics of source rocks, wherein, The method includes: Construct a calculation model for the hydrocarbon expulsion dynamics of each source rock; wherein, the hydrocarbon expulsion dynamics of the source rock include one or more of the following: thermal expansion force of the rock skeleton, hydrothermal expansion force, oil thermal expansion force, gas thermal expansion force, compressive force, product compressive force, clay mineral dehydration force, and diffusion force. Obtain the target layer parameters; Based on the parameters of the target layer, the hydrocarbon expulsion dynamics of each source rock in the target layer are determined by using the calculation model of the hydrocarbon expulsion dynamics of each source rock, thereby realizing the evaluation of the hydrocarbon expulsion dynamics of the source rocks in the target layer. The calculation models for the hydrocarbon expulsion dynamics of each source rock are as follows: In the formula: f The hydrocarbon expulsion force of each source rock is expressed in Pa; μ is the viscosity of the expelled fluid, expressed in Pa·s; Z is the burial depth of the source rock, expressed in meters; ΔQ is the hydrocarbon expulsion velocity per unit volume of source rock. f The volume of liquid discharged by the hydrocarbon source rock, measured in cubic meters (m³). 3 ;△ K W The derivative of the permeability of the source rock discharged fluid, in μm 2 ;△ t The time during which the force acts, measured in seconds (s). The acquisition of target layer parameters includes: Obtain the amount of fluid discharged by the hydrocarbon expulsion dynamics corresponding to the source rock of the target layer; The viscosity of the fluid discharged from the target layer, the burial depth of the source rock in the target layer, the duration of the force applied to the target layer, and the fluid permeability of the source rock in the target layer are obtained.

2. The method according to claim 1, wherein, The computational models for the hydrocarbon expulsion dynamics of various source rocks include: Identify the main factors controlling the hydrocarbon expulsion dynamics of each source rock, and construct a calculation model for the hydrocarbon expulsion dynamics of each source rock based on these main factors.

3. The method according to claim 2, wherein, The main factors controlling hydrocarbon expulsion from each source rock include: The effects of temperature, pressure, permeability, thermal expansion rate of rocks, porosity, density, discharge fluid volume, fluid viscosity, clay mineral content, and illite content of strata at different burial depths on the hydrocarbon discharge dynamics of each source rock were analyzed, and the main factors controlling the hydrocarbon discharge dynamics of each source rock were screened out.

4. The method according to claim 1, wherein, The hydrocarbon expulsion dynamics from the source rock further include oil-water capillary forces; the calculation model for oil-water capillary forces is as follows: In the formula: f 油水毛细管力 This refers to the capillary force between oil and water, in Pa. δ(O) The interfacial tension at the oil-water interface is expressed in N / m. The wetting angle is expressed in degrees (°). r The pore radius of the rock, in units of 10⁻⁶. -10 m.

5. The method according to claim 1, wherein, The hydrocarbon expulsion power from the source rock further includes gas-water capillary force: In the formula: f 气水毛细管力 The force is the capillary force between air and water, in Pa. δ(g) The interfacial tension at the gas-water interface is expressed in N / m. The wetting angle is expressed in degrees (°). r The pore radius of the rock, in units of 10⁻⁶. -10 m.

6. The method according to claim 1, wherein, The amount of fluid discharged by the hydrocarbon source rock corresponding to the target layer hydrocarbon source rock includes: Construct calculation models for the amount of fluid discharged from source rocks due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from source rocks due to the hydrothermal expansion force and / or the amount of fluid discharged from source rocks due to the oil thermal expansion force and / or the amount of fluid discharged from source rocks due to the gas thermal expansion force and / or the amount of fluid discharged from source rocks due to the pressure force and / or the amount of fluid discharged from source rocks due to the product compressibility force and / or the amount of fluid discharged from source rocks due to the clay mineral dehydration force and / or the amount of fluid discharged from source rocks due to the diffusion force. Calculation models based on the amount of fluid discharged from source rocks due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from source rocks due to the hydrothermal expansion force and / or the amount of fluid discharged from source rocks due to the oil thermal expansion force and / or the amount of fluid discharged from source rocks due to the gas thermal expansion force and / or the amount of fluid discharged from source rocks due to the pressure force and / or the amount of fluid discharged from source rocks due to the product compressibility force and / or the amount of fluid discharged from source rocks due to the clay mineral dehydration force and / or the amount of fluid discharged from source rocks due to the diffusion force. The volumetric calculation model determines the amount of fluid discharged from the target layer source rock due to the thermal expansion force of the rock skeleton and / or the amount of fluid discharged from the target layer source rock due to the hydrothermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the oil thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the gas thermal expansion force and / or the amount of fluid discharged from the target layer source rock due to the pressure force and / or the amount of fluid discharged from the target layer source rock due to the product compressibility force and / or the amount of fluid discharged from the target layer source rock due to the clay mineral dehydration force and / or the amount of fluid discharged from the target layer source rock due to the diffusion force.

7. The method according to claim 6, wherein, The calculation model for the amount of fluid discharged from source rocks due to the thermal expansion force of the rock skeleton is as follows: In the formula: This refers to the amount of liquid discharged per unit volume of source rock due to thermal expansion of the rock skeleton, expressed in cubic meters. 3 ; △ K sr ( T ( ) represents the relative change rate of the thermal expansion coefficient of rock with temperature, expressed in % . The surface porosity of the source rock is expressed as % (%). The calculation model for the amount of fluid discharged from the source rock due to hydrothermal expansion is as follows: In the formula: This refers to the amount of liquid discharged per unit volume of source rock due to hydrothermal expansion, expressed in m³. 3 ; S w Water saturation, expressed in % %. K rw ( T () represents the relative rate of change of the hydrothermal expansion coefficient with temperature, expressed in % %. The surface porosity of the source rock is expressed as % (%). The original porosity of the source rock is expressed in % (%). The present porosity of the source rock is expressed in % (%). The calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of oil is as follows: In the formula: This refers to the amount of liquid discharged per unit volume of source rock due to the thermal expansion force of oil, expressed in m³. 3 ; S o Oil saturation, expressed in % (%) K ro ( T ( ) represents the relative change rate of the thermal expansion coefficient of oil with temperature, in % . The surface porosity of the source rock is expressed as % (%). The original porosity of the source rock is expressed in % (%). The present porosity of the source rock is expressed in % (%). The calculation model for the amount of fluid discharged from the source rock due to the thermal expansion force of gas is as follows: In the formula: The volume of liquid discharged per unit volume of source rock due to gas thermal expansion force, expressed in m³. 3 ; S g Gas saturation, in % %. K rg ( P,T () is the gas volume restitution coefficient, with dimensionless units; The surface porosity of the source rock is expressed as % (%). The original porosity of the source rock is expressed in % (%). The present porosity of the source rock is expressed in % (%). The calculation model for the amount of fluid discharged from source rocks due to pressure is as follows: In the formula: This refers to the amount of liquid discharged per unit volume of source rock due to pressure, expressed in cubic meters (m³). 3 ; The surface porosity of the source rock is expressed as % (%). The original porosity of the source rock is expressed in % (%). The present porosity of the source rock is expressed in % (%). The calculation model for the amount of fluid discharged from the source rock due to the compatibilizing force of the products is as follows: In the formula: The fluid volume discharged per unit volume of source rock due to the compatibilizing force of the products, expressed in m³. 3 ; Density of source rock, unit: kg / m³ 3 ; TOC The amount of organic carbon produced per unit mass of source rock during hydrocarbon generation and conversion reactions in geological history, expressed in % (%). R a Oil and gas generation rate, in meters (m³) 3 / t; The calculation model for the amount of fluid discharged from the source rock due to the dehydration force of clay minerals is as follows: In the formula: The fluid volume discharged per unit volume of source rock due to the dehydration force of clay minerals, expressed in m³. 3 ; The content of clay minerals per unit volume of source rock, expressed as % The content of montmorillonite, which undergoes transformation and dehydration in clay minerals, is expressed in % (%). Density of source rock, unit: kg / m³ 3 ; The calculation model for the amount of fluid discharged from the source rock due to diffusion force is as follows: In the formula: The amount of fluid discharged per unit volume of source rock due to diffusion forces, expressed in m³. 3 ; This represents the concentration gradient of oil and gas, in meters (m). 3 / m 3 / m; The diffusion coefficient of natural gas in underground rock is expressed in meters (m). 2 / s; The area of ​​the source rock where diffusion occurred, in meters. 2 ; The time during which the force acts, measured in seconds (s). Porosity of source rocks, in percent.

Images