Lithosphere thermal structure analysis method, apparatus and device, and storage medium

Abstract

The invention discloses a lithosphere thermal structure analysis method, device and equipment and a storage medium, and relates to the technical field of geothermal energy analys.The method comprises the steps that rock information of a current area is obtained, a current lithosphere model is constructed, and the current lithosphere model is composed of a plurality of layers of lithologic units; according to the rock information and a preset temperature change rule, determining a surface earth heat flow value and a lithosphere bottom boundary position corresponding to the current lithosphere model; according to the rock information, determining a hierarchical heat flow value corresponding to each lithologic unit located above the bottom boundary position of the lithosphere, and obtaining a lithosphere heat flow value according to each hierarchical heat flow value; and determining a heat flow ratio parameter as a lithosphere thermal structure analysis result of the current area by combining the earth surface heat flow value and the lithosphere heat flow value. According to the method, the heat flow ratio parameter is obtained by performing layered modeling on the lithosphere, so that accurate quantification of the lithosphere thermal structure is realized from the aspects of heat source properties and a heat transfer mechanism, and the reliability of an analysis result is improved.

Description

Technical Field

[0001] The present application relates to the field of geothermal energy analysis technology, and in particular to a lithosphere thermal structure analysis method, device, equipment and storage medium. Background Art

[0002] Regional thermal structure is a key factor controlling the formation and distribution of underground energy and mineral resources, decisively influencing the occurrence of geothermal resources, oil and gas reservoirs, natural hydrogen, and other energy resources, as well as metal deposits and gemstones. Currently, economically viable resources are primarily concentrated in the shallow crust, where the thermal state is directly regulated by deeper thermodynamic processes such as plate subduction, mantle convection, and lithospheric thinning. The lithosphere, Earth's outermost rigid, solid shell, acts as an insulator for heat transfer from the interior to the surface. Its interaction with the asthenosphere and lower mantle is crucial for understanding Earth's thermodynamics. Therefore, thermal structure analysis can be conducted based on the asthenosphere and lithosphere, emphasizing the pathways of heat transfer from Earth's interior to the surface.

[0003] However, because the lithosphere is composed of the crust and the upper mantle (the lithospheric mantle), and the asthenosphere is also located in the upper mantle, the existing lithospheric thermal structure refers to the distribution ratio and structural relationship of heat flow between the crust and mantle in a region. It is difficult to clearly distinguish between crustal heat flow, lithospheric mantle heat flow, and asthenosphere heat flow from the perspective of heat source properties and heat transfer mechanisms. This leads to cross-confusion of crust-mantle heat flow, which in turn affects the reliability of analytical results determined based on heat flow distribution. Summary of the Invention

[0004] The main purpose of this application is to provide a lithosphere thermal structure analysis method, device, equipment and storage medium, aiming to solve the technical problem of low reliability of existing analysis results determined based on heat flow distribution.

[0005] To achieve the above objectives, the present application proposes a lithosphere thermal structure analysis method, which includes: Obtain rock information of the current area, and construct a current lithosphere model based on the rock information, wherein the current lithosphere model is composed of several layers of lithologic units; Determining the surface terrestrial heat flow value and the bottom boundary position of the lithosphere corresponding to the current lithosphere model according to the rock information and the preset temperature change rule; Determining the layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere according to the rock information, and obtaining the lithosphere heat flow value according to each of the layer heat flow values; A heat flow ratio parameter is determined in combination with the surface terrestrial heat flow value and the lithosphere heat flow value, and the heat flow ratio parameter is determined as the lithosphere thermal structure analysis result of the current region.

[0006] In one embodiment, the rock information includes vertical rock category information, and the step of obtaining the rock information of the current area and constructing the current lithosphere model based on the rock information includes: Initialize the lithosphere hierarchy model and lithologic units based on the standard lithosphere structure; Obtaining vertical rock category information of a current area, where the vertical rock category information is obtained by performing rock survey on the current area; The rock category corresponding to each lithologic unit is determined according to the vertical rock category information, and the lithosphere hierarchical model is labeled based on the rock category correspondence to obtain a current lithosphere model.

[0007] In one embodiment, the rock information further includes: measured temperature data, and the step of determining the surface heat flow value and the lithosphere bottom boundary position corresponding to the current lithosphere model based on the rock information and a preset temperature change rule includes: Determining an average geothermal gradient corresponding to the current lithosphere model according to the measured temperature data and the preset temperature change rule; Based on the average geothermal gradient and the thermal conductivity information of each lithologic unit, obtaining a surface geothermal heat flow value and temperature data of each lithologic unit; A geothermal distribution curve is generated according to the temperature data of each lithologic unit, and the position of the bottom boundary of the lithosphere is obtained according to the geothermal distribution curve.

[0008] In one embodiment, the step of obtaining the surface geothermal flow value and the temperature data of each lithologic unit based on the average geothermal gradient and the thermal conductivity information of each lithologic unit includes: Obtaining thermal conductivity information of each of the lithologic units, and obtaining harmonic thermal conductivity based on the thermal conductivity information, wherein the thermal conductivity information is a measured value of thermal conductivity of each rock type under conditions of the corresponding lithologic unit; Determining a surface terrestrial heat flow value based on the average geothermal gradient and the harmonic thermal conductivity; The heat generation rate information of each of the lithologic units is obtained, and the temperature data of each of the lithologic units is determined layer by layer based on the heat generation rate information, the thermal conductivity information, and the surface geothermal heat flow value.

[0009] In one embodiment, the step of generating a geothermal distribution curve based on the temperature data of each lithologic unit and obtaining the position of the lithosphere bottom boundary based on the geothermal distribution curve includes: generating a geothermal distribution curve according to the temperature data of each of the lithologic units; An intersection analysis is performed on the geothermal distribution curve and at least one standard reference line to obtain a target intersection position, and a corresponding value of the target intersection position is determined as the lithosphere bottom boundary position. The standard reference line includes: a rock solidus line and a mantle adiabatic line.

[0010] In one embodiment, the step of determining the layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere based on the rock information, and obtaining the lithosphere heat flow value based on each of the layer heat flow values, includes: Determining the rock mass thickness of each lithologic unit according to the vertical rock category information; Obtaining heat generation rate information of each lithologic unit, and obtaining a hierarchical heat flow value of each lithologic unit based on the heat generation rate information and the corresponding rock mass thickness; The layer heat flow values ​​corresponding to the lithologic units located above the bottom boundary of the lithosphere are summed to obtain the lithosphere heat flow value.

[0011] In one embodiment, the step of determining the heat flow ratio parameter by combining the surface terrestrial heat flow value and the lithosphere heat flow value includes: Subtracting the lithospheric heat flow value from the surface terrestrial heat flow value to obtain the asthenosphere heat flow value; The heat flow ratio coefficient is obtained by dividing the lithospheric heat flow value by the asthenosphere heat flow value.

[0012] In addition, to achieve the above-mentioned purpose, the present application also proposes a lithosphere thermal structure analysis device, the device comprising: A structural division module is used to obtain rock information of the current area and construct a current lithosphere model based on the rock information, wherein the current lithosphere model is composed of several layers of lithologic units; A first heat flow calculation module is used to determine the surface heat flow value and the bottom boundary position of the lithosphere corresponding to the current lithosphere model based on the rock information and a preset temperature change rule; a second heat flow calculation module, configured to determine, based on the rock information, a layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere, and obtain a lithosphere heat flow value based on each of the layer heat flow values; The quantitative analysis module is used to determine a heat flow ratio parameter by combining the surface earth heat flow value and the lithosphere heat flow value, and determine the heat flow ratio parameter as the lithosphere thermal structure analysis result of the current area.

[0013] In addition, to achieve the above-mentioned purpose, the present application also proposes a lithosphere thermal structure analysis device, which includes: a memory, a processor, and a lithosphere thermal structure analysis program stored in the memory and executable on the processor, wherein the lithosphere thermal structure analysis program is configured to implement the steps of the lithosphere thermal structure analysis method as described above.

[0014] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and stores a lithosphere thermal structure analysis program. When the lithosphere thermal structure analysis program is executed by a processor, the steps of the lithosphere thermal structure analysis method described above are implemented.

[0015] The present application discloses a lithosphere thermal structure analysis method, comprising: obtaining rock information of a current region, and constructing a current lithosphere model based on the rock information, wherein the current lithosphere model is composed of several layers of lithologic units; determining the surface terrestrial heat flow value and the lithosphere bottom boundary position corresponding to the current lithosphere model according to the rock information and preset temperature change rules; determining the hierarchical heat flow value corresponding to each lithologic unit located above the lithosphere bottom boundary position according to the rock information, and obtaining the lithosphere heat flow value according to the heat flow value of each hierarchical layer; determining a heat flow ratio parameter in combination with the surface terrestrial heat flow value and the lithosphere heat flow value, and determining the heat flow ratio parameter as the lithosphere thermal structure analysis result of the current region.

[0016] This application can achieve accurate quantification of the thermal structure of the lithosphere through layered modeling and refined analysis of the lithosphere, and specifically organically combine the asthenosphere heat flow value with the lithosphere heat flow value through heat flow ratio parameters, providing a comprehensive quantitative indicator for the analysis of the thermal structure of the lithosphere, thereby improving the reliability of the analysis results. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 This is a flow chart of the first embodiment of the lithosphere thermal structure analysis method of the present application; Figure 2 This is a flow chart of the second embodiment of the lithosphere thermal structure analysis method of the present application; Figure 3This is a flow chart of the third embodiment of the lithosphere thermal structure analysis method of the present application; Figure 4 This is a schematic diagram of the module structure of the first embodiment of the lithosphere thermal structure analysis device of the present application; Figure 5 This is a schematic diagram of the structure of the lithosphere thermal structure analysis equipment in an embodiment of the present application. DETAILED DESCRIPTION

[0020] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the present application and are not intended to limit the present application.

[0021] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0022] The present invention provides a method for analyzing the thermal structure of the lithosphere. Figure 1 , Figure 1 This is a flow chart of a first embodiment of the lithosphere thermal structure analysis method of the present application. In this embodiment, the method includes steps S10 to S40: Step S10: Obtain rock information of the current area, and construct a current lithosphere model based on the rock information, wherein the current lithosphere model is composed of several layers of lithologic units.

[0023] It should be noted that the execution subject of the method of this embodiment can be a computing electronic device capable of data processing, network communication, and program execution, such as a mobile phone, a personal computer, a lithosphere thermal structure analyzer, etc. Here, a lithosphere thermal structure analyzer (hereinafter referred to as the "analysis device") is used as an example to illustrate this embodiment and the following embodiments.

[0024] It should be understood that the current area is an area where lithospheric thermal structure analysis is required. The rock information of the current area may include vertical rock category information obtained by conducting vertical structural surveys of the area through means such as geological surveys, drilling sampling, and geophysical exploration, such as the collected rock categories, the thickness of each rock category, the distribution range of each rock category, etc.

[0025] Next, based on the acquired rock information, the lithosphere can be divided into several lithologic units. Each lithologic unit represents a rock layer of a certain thickness and specific lithology. For example, a simple lithosphere model might include sedimentary rock layers, granite layers, metamorphic rock layers, and so on, starting from the surface. Parameters for each lithologic unit, such as thickness and rock type, are set based on the actual rock information obtained, thereby constructing a model that reflects the basic structure of the lithosphere in the current region.

[0026] To specifically illustrate the construction process of the current lithosphere model, step S10 may include steps S101 to S103: Step S101: Initialize the lithosphere hierarchy model and each lithologic unit based on the standard lithosphere structure.

[0027] It should be understood that this standard lithospheric structure can be a vertical structural hierarchy from the surface to the base of the lithospheric mantle, obtained based on historical experience. Analysis equipment can directly use this standard lithospheric structure as an initial lithospheric hierarchical model. For example, the lithologic units obtained from a top-down division can be: sedimentary layer, crystalline basement, upper crust, lower crust, and lithospheric mantle.

[0028] Step S102: Obtain vertical rock category information of the current area, where the vertical rock category information is obtained by performing rock survey on the current area.

[0029] Step S103: determining the rock category corresponding to each lithologic unit according to the vertical rock category information, and labeling the lithosphere hierarchical model based on the rock category correspondence to obtain a current lithosphere model.

[0030] It should be understood that since the vertical depth that can be collected by surveying means is limited, the current area can be divided vertically into shallow and deep strata, and the shallow strata can be identified with high precision, and the deep strata can be predicted with high precision.

[0031] For high-precision identification of shallow strata, direct exploration techniques can be used to drill and coring areas where drilling conditions permit. Core testing and analysis (such as isotope dating, geochemical analysis, and mineral identification) and / or well logging can be used to accurately calibrate the age and lithology of the formations. In areas where drilling data is scarce, geophysical methods such as gravity, magnetics, electrical methods, and seismic exploration can be combined to effectively identify geological structural units and their spatial distribution characteristics through single or multiple inversion methods.

[0032] When making high-precision predictions of deep strata, due to the limitations of current drilling technology, it is impossible to directly obtain physical data of strata deeper than 10 km. Therefore, indirect high-precision analytical or collaborative inversion techniques can be used to predict deep vertical structures. Indirect high-precision analytical techniques can include seismic exploration, electromagnetic exploration, and gravity exploration.

[0033] Seismic exploration technology involves artificially stimulating elastic waves. As these waves propagate through underground strata, they can reflect and refract upon encountering different rock interfaces or structures. By analyzing and processing the propagation characteristics of these elastic waves (such as the travel time, amplitude, and frequency of the reflected waves), the locations of deep strata interfaces, structural morphology, and the elastic properties of the rocks can be inferred.

[0034] Electromagnetic exploration technology detects fluids based on differences in rock electrical properties. When fluid-bearing intervals exist within the subsurface rock, the significantly different electrical conductivity of the fluids from the surrounding rock produces a significant response to electromagnetic fields. By measuring the changing characteristics of the electromagnetic field, the location and distribution of these fluid-bearing intervals can be identified.

[0035] Gravity exploration technology infers the density distribution of underground rocks by measuring anomalous changes in the Earth's gravity field. Different rock types have different densities, and changes in the composition of deep-lying materials can cause gravity field anomalies. By analyzing gravity anomaly data, the density structure of underground rocks can be inferred, and further, the changes in the composition of deep strata and the distribution of geological structures can be inferred.

[0036] Joint inversion based on the above technologies can achieve the fusion of multi-physical field data and comprehensively utilize various geophysical information to complement and verify each other, thereby improving the reliability and resolution of deep structure imaging.

[0037] In specific implementation, through high-precision identification of shallow strata and high-precision prediction of deep strata, the rock categories corresponding to each lithologic unit can be obtained and the model can be labeled: sedimentary layer (sedimentary rock), crystalline basement (metamorphic rock / igneous rock), upper crust (mainly granite / basalt) and lower crust (mainly granulite facies / gabbro), and lithospheric mantle (mainly peridotite).

[0038] It should be understood that representative samples of each lithologic unit can also be collected to measure its thermophysical properties, including density, thermal conductivity, and heat generation rate. For shallow rock masses with drilling capabilities, complete core samples can be obtained. For shallow and deep rock masses without drilling capabilities, fresh surface outcrop samples of the same lithologic structure can be collected through field surveys.

[0039] The density test may be: testing the density of the rock sample by using a helium pycnometer method, an Archimedes method, or the like.

[0040] Thermal conductivity testing can be done by using the mobile heat source method, laser flash method, transient plate heat source method, probe method, etc. To obtain underground in-situ thermal conductivity, the collected rock samples can be saturated with water, pressurized, and heated to simulate in-situ conditions for testing. If pressurization and heating conditions are unavailable, empirical formulas proposed by predecessors can be used for correction.

[0041] The heat generation rate calculation process can be: Testing the main radioactive decay elements in rocks by inductively coupled plasma mass spectrometry (ICP-MS) 238 U. 232 Th and 40 K content, using the empirical formula to calculate the heat generation rate: A=0.01 (9.52C U +2.56C Th +3.48C K ), where A is the heat generation rate, and the unit is W / m3; is the density in g / cm 3 ; C U is the uranium content in the rock, g / g; C Th is the thorium content in the rock, in units of g / g; C K It is the potassium content in the rock, in %.

[0042] According to the measurement results of the above-mentioned thermophysical parameters, the thermophysical parameters corresponding to each hierarchical unit in the lithosphere hierarchical model can also be marked respectively, and the current lithosphere model can be obtained after marking.

[0043] It should also be noted that since the traditional standard definition of the lithosphere includes the entire crust and the top of the upper mantle, the bottom layer of the current lithosphere model determined based on survey data may not necessarily be the boundary between the top of the upper mantle and the asthenosphere in the standard definition. Therefore, the current lithosphere model can be regarded as a rough model of the lithosphere in the current region.

[0044] Step S20: Determine the surface heat flow value and the bottom boundary position of the lithosphere corresponding to the current lithosphere model according to the rock information and the preset temperature change rule.

[0045] It should be noted that the preset temperature variation rule may be a geothermal gradient variation rule determined based on geothermal theory and empirical formulas. The geothermal gradient is the rate at which temperature changes with depth. Under normal circumstances, the geothermal gradient has a certain average value and range of variation. Rocks of different lithologies may have different geothermal gradient characteristics, and the heat generation rate generated by the decay of radioactive elements in the rock can also affect the temperature distribution.

[0046] The surface heat flow is equal to the sum of the crustal heat flow and the mantle heat flow. It reflects the amount of heat transferred from the Earth's interior through the lithosphere to the surface and is a key parameter in analyzing the thermal structure of the lithosphere. The surface heat flow value can be determined based on the geothermal gradient and combined with rock information (such as thermal conductivity and heat generation rate). Using mathematical models such as the heat conduction equation, the temperature distribution downward from the surface can be calculated.

[0047] In the specific implementation, the measured temperature data from the near-surface isothermal zone to a part of the underground lithologic unit can be obtained first, and then the average geothermal gradient can be calculated according to the geothermal gradient change rule; and the harmonic thermal conductivity of this part of the lithosphere can be estimated based on the thermal conductivity corresponding to each rock type in this part measured above; finally, the surface geothermal heat flow value can be calculated based on the average geothermal gradient and harmonic thermal conductivity of this part.

[0048] It should also be noted that due to the uncertainty of the vertical depth collected by survey means, in order to conduct thermal structure analysis of the lithosphere from the perspective of heat source and heat transfer mechanism, we can first determine the bottom boundary of the lithosphere in the current area, that is, the boundary between the top of the upper mantle and the asthenosphere in the current area, so as to determine the specific boundary position between the lithosphere and the asthenosphere in the current lithosphere model.

[0049] In practice, the bottom of the lithosphere can be determined when the temperature curve reaches a certain condition (such as the temperature characteristic of the top of the asthenosphere or the temperature at which rocks begin to partially melt). For example, based on the solidus temperature of rock (the temperature at which rock begins to melt), the bottom of the lithosphere is determined at the depth where the calculated temperature distribution curve reaches that temperature.

[0050] Step S30: determining the layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere according to the rock information, and obtaining the lithosphere heat flow value according to each of the layer heat flow values.

[0051] It should be noted that in the current lithosphere model, for each lithologic unit above the bottom boundary of the lithosphere, the hierarchical heat flow value of each lithologic unit can be calculated based on its rock information (such as heat generation rate, thickness, etc.) and temperature distribution.

[0052] The layer-level heat flow value represents the heat contribution of each lithologic unit to the lithospheric thermal structure. For example, if the thickness and corresponding heat generation rate of a lithologic unit are known, the layer-level heat flow value of that lithologic unit can be calculated.

[0053] In the specific implementation, the hierarchical heat flow values ​​of the lithologic units in the current lithosphere model are calculated layer by layer. The calculation range is from the top layer of the current lithosphere model to the bottom boundary of the lithosphere. The heat flow values ​​of each layer are accumulated and summed to obtain the total heat flow generated by the heat release of rocks within the lithosphere range in the standard definition, that is, the lithosphere heat flow value.

[0054] Step S40: determining a heat flow ratio parameter in combination with the surface earth heat flow value and the lithosphere heat flow value, and determining the heat flow ratio parameter as the lithosphere thermal structure analysis result of the current region.

[0055] It should be noted that in order to achieve accurate distinction of heat flow properties by strictly distinguishing between the lithospheric heat flow dominated by conduction (radioactive heat generation) and the asthenospheric heat flow dominated by convection (deep thermal energy), the surface heat flow can be divided into lithospheric heat flow and asthenospheric heat flow.

[0056] It should be understood that the heat flow ratio parameter is derived by comparing the lithospheric heat flow with the asthenosphere heat flow. This parameter redefines the lithospheric thermal structure from the perspective of heat flow distribution. Compared with the traditional crust-mantle heat flow ratio method, it can more accurately reflect the thermodynamic coupling relationship of the lithosphere-asthenosphere system.

[0057] In practice, the asthenosphere heat flow value can be obtained by subtracting the lithospheric heat flow value from the surface heat flow value. This heat flow value can then be divided by the asthenosphere heat flow value to obtain the heat flow ratio coefficient, which serves as the lithospheric thermal structure analysis result for the current region. This result can be used to assess the thermal state and thermal evolution of the lithosphere, as well as its relationship to tectonic activity. For example, different heat flow ratio parameter ranges may correspond to different lithosphere types (e.g., stable continental lithosphere, active lithosphere) or tectonic settings (e.g., plate subduction zones, hotspots, etc.), providing important reference for geological research, resource exploration, and other related fields.

[0058] This embodiment establishes a new quantitative analysis method based on the essence of thermodynamics by strictly distinguishing between the conduction-dominated lithospheric heat flow (radioactive heat generation) and the convection-dominated asthenosphere heat flow (deep thermal energy): through layered modeling and refined analysis of the lithosphere, accurate quantification of the lithosphere thermal structure is achieved, and specifically through the heat flow ratio parameter, the surface geothermal heat flow value and the lithosphere heat flow value are organically combined, providing a comprehensive quantitative indicator for the analysis of the lithosphere thermal structure, thereby improving the reliability of the analysis results.

[0059] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above embodiment 1 can be referred to the above introduction and will not be described in detail later. Figure 2 , Figure 2This is a flow chart of the second embodiment of the lithosphere thermal structure analysis method of the present application.

[0060] In this embodiment, in order to specifically illustrate how to determine the surface heat flow value and the bottom boundary of the lithosphere, step S20 includes: steps S201 to S203: Step S201: determining the average geothermal gradient corresponding to the current lithosphere model according to the measured temperature data and the preset temperature variation rule.

[0061] It should be understood that the aforementioned rock information may also include measured temperature data, which may be temperature data from a near-surface constant temperature zone to a portion of underground lithologic units obtained by direct or indirect measurement.

[0062] For example, temperature measurement can be carried out directly in the drilling area: steady-state temperature measurement of the system is carried out through a thermistor thermometer to obtain vertical continuous temperature data; for the non-drilling area, indirect temperature measurement can be used: temperature data can be obtained through geophysical detection (magnetotellurics, seismic wave velocity changes, etc.), geochemical temperature scales (SiO2 thermometers, cation thermometers, gas chemical thermometers, isotope thermometers, etc.) or remote sensing (infrared radiation thermometry).

[0063] The preset temperature variation rule refers to the temperature variation with depth, determined based on geothermal theory and experience. Therefore, after obtaining measured temperature data, the temperature increase can be calculated based on the data volume, using the temperature variation rule per hundred meters or kilometers (the temperature change interval can be reduced to the meter level). This allows the calculation of the average geothermal gradient from the surface to the bottom of the measurement. This also determines whether the steady-state temperature curve exhibits linear variation. If nonlinear variation is present, convection should be considered.

[0064] Step S202: Based on the average geothermal gradient and the thermal conductivity information of each lithologic unit, obtain the surface geothermal flow value and the temperature data of each lithologic unit.

[0065] It should be understood that in terrain structures composed of multiple layers of rock, the harmonic thermal conductivity is an average value obtained by comprehensively considering the thickness and thermal conductivity of each rock layer. This value better reflects the thermal conductivity characteristics of the entire formation. The harmonic mean of the current lithospheric model can be calculated by taking the harmonic mean of the thermal conductivity of each rock type (that is, the sum of the thickness of each layer divided by the corresponding thermal conductivity, and then dividing by the total thickness).

[0066] It's easy to understand that, according to Fourier's law of heat conduction, the surface heat flow is equal to thermal conductivity multiplied by the geothermal gradient. This refers to the heat flow from the Earth's interior to the surface, and is equal to the average thermal conductivity from the near-surface constant temperature zone to the subsurface, multiplied by the average geothermal gradient. Therefore, by substituting the calculated harmonic thermal conductivity and average geothermal gradient values, we can calculate the surface heat flow, which reflects the amount of heat transferred from the Earth's interior to the surface per unit area.

[0067] It should also be noted that for lithologic units in the current lithospheric model that do not have corresponding measured temperatures, deep temperatures cannot be directly obtained due to drilling limitations. Therefore, they can be obtained indirectly through methods such as steady-state equation derivation, geophysical inversion, and mantle xenolith constraints.

[0068] It should be understood that starting from the surface, the temperature distribution within each lithologic unit can be calculated layer by layer using the surface geothermal heat flow value, combined with the heat generation rate and thermal conductivity information of each lithologic unit, according to the heat conduction equation. For example, in the case of steady-state heat conduction, the temperature at the bottom of the current layer can be calculated based on the temperature of the bottom boundary of the previous layer, the heat generation rate, thermal conductivity, and thickness of the current layer, and so on, to obtain the temperature data of each lithologic unit.

[0069] In addition, the temperature can be obtained through the correlation between seismic wave velocity and temperature proposed by predecessors, partial melting constraints can be constrained through electromagnetic methods, or the Curie point temperature can be determined based on the demagnetization temperature of the mineral, as well as the temperature can be estimated using empirical formulas through olivine, spinel, etc. in mantle inclusions, thereby obtaining temperature data for each lithologic unit.

[0070] In a specific implementation, the thermal conductivity information of each lithologic unit from the near-surface isothermal zone to a part of the underground can be obtained first, and the harmonic thermal conductivity can be obtained based on the thermal conductivity information; then, the surface geothermal heat flow value can be determined according to the average geothermal gradient and the harmonic thermal conductivity; finally, the heat generation rate information of each lithologic unit can be obtained, and the temperature data of each lithologic unit can be determined layer by layer according to the heat generation rate information, thermal conductivity information and surface geothermal heat flow value.

[0071] Step S203: generating a geothermal distribution curve according to the temperature data of each lithologic unit, and obtaining the position of the bottom boundary of the lithosphere according to the geothermal distribution curve.

[0072] It should be noted that the base of the lithosphere is the interface between the lithosphere and the asthenosphere. At this location, the physical and thermodynamic properties of the lithosphere change significantly: the rocks at the base of the lithosphere are relatively hard, while the materials in the asthenosphere have a certain plasticity and can undergo slow deformation and flow.

[0073] It should be understood that the temperature data of each lithologic unit can be arranged in order of depth, with temperature as the horizontal axis and depth as the vertical axis (or vice versa), to plot a geothermal distribution curve. This geothermal distribution curve intuitively shows the trend of underground temperature variation with depth and reflects the temperature field characteristics within the lithosphere.

[0074] Next, by analyzing the geothermal distribution curve and combining it with the temperature characteristics of the lithosphere base (such as the temperature at the top of the asthenosphere or the temperature at which partial melting of rocks begins), we can determine the depth at which the curve reaches that temperature characteristic, which is the location of the lithosphere base. For example, if the temperature at the top of the asthenosphere is known to be approximately a certain value, then the corresponding depth when the geothermal distribution curve reaches or approaches that temperature is the depth of the lithosphere base.

[0075] In a specific implementation, the geothermal distribution curve and at least one standard reference line (rock solidus or mantle adiabatic line) can be drawn in the same coordinate system, and the intersection between them can be observed and analyzed to obtain the target intersection position, and the corresponding value of the target intersection position can be determined as the bottom boundary position of the lithosphere.

[0076] The solidus of a rock refers to the temperature curve at which a rock begins to melt under different pressures. It represents the temperature-pressure relationship at which a rock transitions from a solid state to a solid-liquid mixture under specific geological conditions. Different rock types, such as granite and basalt, have different solidus curves. For example, the solidus temperature of dry basalt is typically higher than that of basalt containing water, because volatiles such as water can lower the rock's melting point.

[0077] The mantle adiabatic curve is a graph showing the temperature variation with depth during adiabatic ascent or descent of mantle material. Adiabatic processes mean that the mantle material does not exchange heat with its surroundings, and temperature changes are caused solely by its own compression or expansion. The slope of the mantle adiabatic curve depends primarily on the physical properties of the mantle material, such as its coefficient of thermal expansion and specific heat capacity. The temperature of a normal mantle adiabatic curve increases with depth, but the magnitude of this increase is smaller than that of the geothermal gradient.

[0078] By rationally utilizing measured temperature data and adhering to pre-set temperature variation rules, this embodiment scientifically calculates the average geothermal gradient, which serves as the basis for subsequent heat flow calculations and thermal structure analysis, ensuring the reliability of the underlying data. Furthermore, the method of determining the lithosphere base through intersection analysis between the generated geothermal distribution curve and a standard reference line provides a clear and objective basis for defining the lithosphere base, making the determination of the lithosphere base more consistent with actual geological conditions and significantly enhancing the scientific nature and credibility of the lithosphere thermal structure analysis results.

[0079] Based on the first and second embodiments of the present application, in the third embodiment of the present application, the same or similar contents as those in the first and second embodiments can be referred to above and will not be described in detail. Figure 3 , Figure 3 This is a flow chart of the third embodiment of the lithosphere thermal structure analysis method of the present application.

[0080] In this embodiment, in order to specifically illustrate how to calculate the lithospheric heat flow value after determining the lithosphere bottom boundary, step S30 specifically includes: steps S301 to S303: Step S301: Determine the rock mass thickness of each lithologic unit according to the vertical rock category information.

[0081] Step S302: Obtain heat generation rate information of each lithologic unit, and obtain the hierarchical heat flow value of each lithologic unit based on the heat generation rate information and the corresponding rock mass thickness.

[0082] It should be understood that, based on the aforementioned vertical rock category information, the rock thickness of each lithologic unit in the current lithosphere model can be obtained; and based on the aforementioned sample tests on each lithologic unit, the heat generation rate measurement value of each lithologic unit can be obtained.

[0083] In specific implementation, the hierarchical heat flow value of each lithologic unit can be calculated based on the heat generation rate and rock thickness of each lithologic unit. The calculation formula is: hierarchical heat flow value = heat generation rate Rock mass thickness.

[0084] Step S303: summing the hierarchical heat flow values ​​corresponding to the lithologic units located above the bottom boundary of the lithosphere to obtain the lithosphere heat flow value.

[0085] It should be understood that in the current lithosphere model, the lithologic units located above the bottom boundary of the lithosphere constitute the lithosphere in the standard definition. Then, by summing the heat flow values ​​of the above-mentioned lithologic units, the lithosphere heat flow value can be obtained, which represents the total heat flow generated by the radioactive heating of rocks within the standard lithosphere range.

[0086] Furthermore, after obtaining the lithospheric heat flow, the difference between it and the aforementioned surface heat flow can be determined as the asthenospheric heat flow, thereby quantitatively determining the lithospheric thermal structure of the current area by obtaining the thermal ratio coefficient by dividing the lithospheric heat flow by the asthenospheric heat flow.

[0087] Specifically, the thermal distribution ratio reflects the relationship between surface and lithosphere heat flow, while the structure of the lithosphere influences shallow geothermal fields and the distribution of energy and mineral resources. The thickness and internal structure of the lithosphere control geothermal gradients and heat flow distribution, respectively, and are directly related to the formation mechanism of the thermal distribution ratio. A comprehensive analysis of the lithosphere structure, combined with the thermal distribution ratio, can provide a deep understanding of shallow thermal conditions, providing key insights for underground energy and mineral exploration and development.

[0088] For example, lithosphere thickness influences shallow geothermal fields and alters the geothermal gradient: when the lithosphere is thinner, the deep heat flow path is shortened, increasing the geothermal gradient; when it is thicker, the path is extended, decreasing the geothermal gradient. This primarily reflects the influence of asthenospheric heat flow, which is closely related to the asthenospheric heat flow contribution in the heat distribution ratio. The heat distribution ratio reflects the impact of these thickness differences on shallow thermal conditions, helping to understand geothermal field variations.

[0089] The thickness of lithologic layers within the lithosphere and their heat generation rate jointly determine the vertical distribution of heat flow. High-heat-generating or thick rock layers significantly increase the contribution to heat flow, raising ground temperatures. The heat ratio reflects the relationship between heat flow in the hot lithosphere and surface heat flow, and its magnitude is influenced by the internal structure of the hot lithosphere. When analyzing the heat ratio, it is important to consider the modulation of heat flow by internal structure to accurately assess the impact of the hot lithosphere on the thermal state of shallow formations.

[0090] Furthermore, the complex matching relationship between heat flow in the asthenosphere and lithosphere under actual geological conditions leads to regional variations in shallow geothermal fields. Different energy minerals have different thermal requirements. Therefore, using heat matching values ​​to reflect the differences in heat flow coupling under the influence of thermal lithosphere structure can provide a key basis for the evaluation of energy minerals (such as oil and gas systems, metal deposits, and geothermal resources).

[0091] This example, by identifying the boundary between the lithosphere and asthenosphere, or the lithosphere base, divides the heat flow in the current region into two distinct thermodynamic units: the lithosphere and the asthenosphere, based on their thermodynamic nature. This allows for lithospheric structural analysis. The hierarchical heat flow values ​​corresponding to each lithologic unit above the lithosphere base are then summed to obtain the lithosphere heat flow value. This allows for the subsequent development of a quantitative heat flow ratio characterization system based on the ratio of the lithosphere heat flow value to the asthenosphere heat flow value. This allows for a strict distinction between conductive heat flow (radiative heating of the crust and mantle) and convective heat flow (deep heat input), establishing a structural delineation standard based on thermodynamic mechanisms and avoiding the cross-confusion of crust and mantle heat flow in traditional definitions.

[0092] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the lithosphere thermal structure analysis method of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0093] The present application also provides a lithosphere thermal structure analysis device, please refer to Figure 4 , Figure 4 This is a schematic diagram of the module structure of the lithosphere thermal structure analysis device of the present application, which includes: The structural division module 401 is used to obtain rock information of the current area and construct a current lithosphere model based on the rock information. The current lithosphere model is composed of several layers of lithologic units. A first heat flow calculation module 402 is configured to determine the surface heat flow value and the bottom boundary position of the lithosphere corresponding to the current lithosphere model based on the rock information and a preset temperature change rule; A second heat flow calculation module 403 is configured to determine, based on the rock information, a layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere, and obtain a lithosphere heat flow value based on each of the layer heat flow values; The quantitative analysis module 404 is used to determine a heat flow ratio parameter based on the surface earth heat flow value and the lithosphere heat flow value, and determine the heat flow ratio parameter as the lithosphere thermal structure analysis result of the current region.

[0094] This example establishes a new quantitative analysis method based on the essence of thermodynamics by strictly distinguishing between conduction-dominated lithospheric heat flow (radiative heating) and convection-dominated asthenosphere heat flow (deep thermal energy). Compared to existing methods and technologies, this example achieves precise differentiation of heat flow properties, avoiding the heat flow confusion problem in traditional research. By establishing a quantitative characterization system for heat flow ratios, it provides a new analytical framework for deep thermal structure research. By revealing the detailed characteristics of heat source composition and heat transfer pathways, it significantly improves the prediction accuracy of resource exploration for oil and gas, geothermal, and metal deposits, providing innovative theoretical foundations and technical support for mineral resource exploration.

[0095] The present application also provides a lithosphere thermal structure analysis device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the lithosphere thermal structure analysis method in the above-mentioned embodiment one.

[0096] Reference below Figure 5 , Figure 5This is a schematic diagram of the structure of the lithosphere thermal structure analysis device of the present application. The lithosphere thermal structure analysis device in the embodiments of the present application may include, but is not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), and fixed terminals such as digital TVs and desktop computers. Figure 5 The lithosphere thermal structure analysis device shown is merely an example and should not limit the functions and scope of use of the embodiments of the present application.

[0097] like Figure 5 As shown, the lithosphere thermal structure analysis device may include a processor 1001 (e.g., a central processing unit, graphics processing unit, etc.), which can execute various appropriate actions and processes based on programs stored in a read-only memory (ROM) 1002 or programs loaded from a storage device 1003 into a random access memory (RAM) 1004. RAM 1004 also stores various programs and data required for the operation of the lithosphere thermal structure analysis device. Processor 1001, ROM 1002, and RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems may be connected to I / O interface 1006: input devices 1007, such as a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008, such as a liquid crystal display (LCD), speaker, vibrator, etc.; storage device 1003, such as a magnetic tape or hard disk; and communication devices 1009. The communication device 1009 can allow the lithosphere thermal structure analysis device to communicate wirelessly or wired with other devices to exchange data. Although the figure shows a lithosphere thermal structure analysis device with various systems, it should be understood that it is not required to implement or have all of the systems shown. More or fewer systems may be implemented or have alternatively.

[0098] The lithosphere thermal structure analysis device provided in this application utilizes the lithosphere thermal structure analysis method described in the aforementioned embodiment to address the technical challenges of lithosphere thermal structure analysis. Compared to the prior art, the lithosphere thermal structure analysis device provided in this application offers the same beneficial effects as the lithosphere thermal structure analysis method described in the aforementioned embodiment. Other technical features of the lithosphere thermal structure analysis device are the same as those disclosed in the aforementioned embodiment and are not further detailed here.

[0099] The present application also provides a computer-readable storage medium having computer-readable program instructions (ie, a computer program) stored thereon, the computer-readable program instructions being used to execute the lithosphere thermal structure analysis method in the above-mentioned embodiment.

[0100] The computer-readable storage medium provided herein may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems, or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including, but not limited to, wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0101] The computer-readable storage medium provided in this application stores computer-readable program instructions (i.e., a computer program) for executing the aforementioned lithosphere thermal structure analysis method, thereby solving the technical problems associated with lithosphere thermal structure analysis. Compared to the prior art, the computer-readable storage medium provided in this application offers the same beneficial effects as the lithosphere thermal structure analysis method provided in the aforementioned embodiments, and therefore will not be further elaborated upon here.

[0102] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or system. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional elements in the process, method, article, or system comprising the element.

[0103] The serial numbers of the above-mentioned embodiments of the present invention are for description only and do not represent the advantages or disadvantages of the embodiments. They are only some embodiments of the present application and do not limit the scope of the present application. All equivalent structural transformations made by using the contents of the description and drawings of the present application under the technical concept of the present application, or direct / indirect application in other related technical fields are included in the scope of protection of the present application.

Claims

1. A method for analyzing the thermal structure of the lithosphere, characterized in that: The method comprises: Obtain rock information of the current area, and construct a current lithosphere model based on the rock information, wherein the current lithosphere model is composed of several layers of lithologic units; Determining the surface terrestrial heat flow value and the bottom boundary position of the lithosphere corresponding to the current lithosphere model according to the rock information and the preset temperature change rule; Determining the layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere according to the rock information, and obtaining the lithosphere heat flow value according to each of the layer heat flow values; A heat flow ratio parameter is determined in combination with the surface terrestrial heat flow value and the lithosphere heat flow value, and the heat flow ratio parameter is determined as the lithosphere thermal structure analysis result of the current region.

2. The method according to claim 1, wherein The rock information includes vertical rock category information. The step of obtaining the rock information of the current area and constructing the current lithosphere model based on the rock information includes: Initialize the lithosphere hierarchy model and lithologic units based on the standard lithosphere structure; Obtaining vertical rock category information of a current area, where the vertical rock category information is obtained by performing rock survey on the current area; The rock category corresponding to each lithologic unit is determined according to the vertical rock category information, and the lithosphere hierarchical model is labeled based on the rock category correspondence to obtain a current lithosphere model.

3. The method according to claim 1, wherein The rock information further includes: measured temperature data. The step of determining the surface heat flow value and the bottom boundary position of the lithosphere corresponding to the current lithosphere model based on the rock information and a preset temperature change rule includes: Determining an average geothermal gradient corresponding to the current lithosphere model according to the measured temperature data and the preset temperature change rule; Based on the average geothermal gradient and the thermal conductivity information of each lithologic unit, obtaining a surface geothermal heat flow value and temperature data of each lithologic unit; A geothermal distribution curve is generated according to the temperature data of each lithologic unit, and the position of the bottom boundary of the lithosphere is obtained according to the geothermal distribution curve.

4. The method according to claim 3, wherein The step of obtaining the surface geothermal flow value and the temperature data of each lithologic unit based on the average geothermal gradient and the thermal conductivity information of each lithologic unit comprises: Obtaining thermal conductivity information of each of the lithologic units, and obtaining harmonic thermal conductivity based on the thermal conductivity information, wherein the thermal conductivity information is a measured value of thermal conductivity of each rock type under conditions of the corresponding lithologic unit; Determining a surface terrestrial heat flow value based on the average geothermal gradient and the harmonic thermal conductivity; The heat generation rate information of each of the lithologic units is obtained, and the temperature data of each of the lithologic units is determined layer by layer based on the heat generation rate information, the thermal conductivity information, and the surface geothermal heat flow value.

5. The method according to claim 3, wherein The step of generating a geothermal distribution curve based on the temperature data of each lithologic unit and obtaining the position of the lithosphere bottom boundary based on the geothermal distribution curve comprises: generating a geothermal distribution curve according to the temperature data of each of the lithologic units; An intersection analysis is performed on the geothermal distribution curve and at least one standard reference line to obtain a target intersection position, and a corresponding value of the target intersection position is determined as the lithosphere bottom boundary position. The standard reference line includes: a rock solidus line and a mantle adiabatic line.

6. The method according to claim 2, wherein The step of determining the layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere based on the rock information, and obtaining the lithosphere heat flow value based on each of the layer heat flow values, comprises: Determining the rock mass thickness of each lithologic unit according to the vertical rock category information; Obtaining heat generation rate information of each lithologic unit, and obtaining a hierarchical heat flow value of each lithologic unit based on the heat generation rate information and the corresponding rock mass thickness; The layer heat flow values ​​corresponding to the lithologic units located above the bottom boundary of the lithosphere are summed to obtain the lithosphere heat flow value.

7. The method according to claim 1, wherein The step of determining the heat flow ratio parameter by combining the surface earth heat flow value and the lithosphere heat flow value comprises: Subtracting the lithospheric heat flow value from the surface terrestrial heat flow value to obtain the asthenosphere heat flow value; The heat flow ratio coefficient is obtained by dividing the lithospheric heat flow value by the asthenosphere heat flow value.

8. A lithosphere thermal structure analysis device, characterized in that: The device comprises: A structural division module is used to obtain rock information of the current area and construct a current lithosphere model based on the rock information, wherein the current lithosphere model is composed of several layers of lithologic units; A first heat flow calculation module is used to determine the surface heat flow value and the bottom boundary position of the lithosphere corresponding to the current lithosphere model based on the rock information and a preset temperature change rule; a second heat flow calculation module, configured to determine, based on the rock information, a layer heat flow value corresponding to each of the lithologic units located above the bottom boundary of the lithosphere, and obtain a lithosphere heat flow value based on each of the layer heat flow values; The quantitative analysis module is used to determine a heat flow ratio parameter by combining the surface earth heat flow value and the lithosphere heat flow value, and determine the heat flow ratio parameter as the lithosphere thermal structure analysis result of the current area.

9. A lithosphere thermal structure analysis device, characterized in that: The device includes a memory, a processor, and a lithosphere thermal structure analysis program stored in the memory and executable on the processor. When the lithosphere thermal structure analysis program is executed by the processor, the steps of the lithosphere thermal structure analysis method according to any one of claims 1 to 7 are implemented.

10. A storage medium, characterized in that: The storage medium stores a lithosphere thermal structure analysis program, which, when executed by a processor, implements the steps of the lithosphere thermal structure analysis method according to any one of claims 1 to 7.

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