Method, device, equipment and storage medium for establishing deep temperature field of geothermal resources

Abstract

The present invention provides a method, device, equipment and storage medium for establishing a deep temperature field of geothermal resources, the method comprising: constructing a geological model of a target study area; based on the geological model, dividing the target study area into a plurality of continuous layers, and dividing each target layer into a plurality of continuous sub-layers; wherein the target layer is any layer, and the lithology of each target layer is the same; taking the surface temperature as the starting point of temperature calculation, and calculating the temperature of each sub-layer in turn based on each geological parameter in a geological parameter database and a preset temperature calculation formula; wherein the geological parameter database includes at least surface heat flow value, rock thermal conductivity, rock heat generation rate and sub-layer thickness; based on the temperature of all sub-layers at different depths, determining the temperature field distribution map of the target study area. The present invention can improve the accuracy of establishing a deep temperature field of geothermal resources.

Description

Technical Field

[0001] The present invention relates to the field of geothermal resource technology, and in particular to a method, device, equipment and storage medium for establishing a deep temperature field of geothermal resources. Background Art

[0002] Geothermal resources are abundant and pollution-free clean energy, generally concentrated in the margins of tectonic plates, and mostly originate from the decay of molten magma and radioactive substances in the earth. As traditional energy sources such as oil and coal are gradually exhausted, geothermal resources will become an important way to alleviate the energy crisis in the future.

[0003] The deep underground temperature plays a vital role in the assessment and development of geothermal resources. There are two methods for measuring temperature, direct measurement and indirect measurement. The direct measurement method is the most accurate method, but it requires drilling. However, for a large number of areas where there are no drillings, the deep temperature cannot be measured directly. Indirect measurement mainly predicts the geothermal field indirectly through geochemical or geophysical means. Geochemical means mainly use geochemical geothermometers to predict the temperature field. This type of indirect geothermometer can predict the distribution range of heat reservoir temperature. Geophysical detection geothermometers currently mainly use underground detection technology and purely empirical formulas to construct the correlation between physical parameters and temperature, and then use inverted geophysical parameters to infer the temperature field.

[0004] However, direct measurement methods must be obtained through drilling, and geochemical thermometers cannot provide regional temperature distribution and it is difficult to match predicted temperature with depth. The effectiveness of geothermal thermometers for geophysical detection is usually assumed to be independent of spatial location, but geophysics is multi-solutionable, and the same phenomenon may be caused by different reasons. How to accurately calculate underground temperature to meet the needs of geothermal resource evaluation has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] The embodiments of the present invention provide a method, device, equipment and storage medium for establishing a deep temperature field of geothermal resources to solve the problem that the current geothermal temperature calculation method is inaccurate.

[0006] In a first aspect, an embodiment of the present invention provides a method for establishing a deep temperature field of geothermal resources, comprising:

[0007] Construct a geological model of the target study area; the geological model is used to visualize the strata, fracture structures and lithology of the target study area;

[0008] Based on the geological model, the target research area is divided into multiple continuous layers, and each target layer is divided into multiple continuous sub-layers; wherein the target layer is any layer, and the lithology of each target layer is the same;

[0009] Taking the surface temperature as the starting point of temperature calculation, the temperature of each sub-layer is calculated in turn based on the geological parameters in the geological parameter database and the preset temperature calculation formula; wherein the geological parameter database at least includes the surface heat flow value, rock thermal conductivity, rock heat generation rate and sub-layer thickness;

[0010] Based on the temperatures of all sub-layers at different depths, the temperature field distribution map of the target study area is determined.

[0011] In a possible implementation, based on the geological model, the target study area is divided into a plurality of continuous layers, and each target layer is divided into a plurality of continuous sub-layers, including:

[0012] Based on the geological model, the target study area is divided into multiple continuous layers; each layer has different thermophysical parameters, including thermal conductivity and heat generation rate;

[0013] Based on the thickness of the target layer and the preset accuracy, the target layer is divided into a plurality of sub-layers with the same thickness.

[0014] In one possible implementation, a geological model of a target study area is constructed, including:

[0015] A geological model of the target study area is constructed based on the zoned stratigraphic table, drilling measurement data, seismic detection data and wide-area electromagnetic measurement results of the target study area.

[0016] In a possible implementation, if the target sub-layer is sedimentary rock, the preset temperature calculation formula of the sub-layer is:

[0017] T(I n J n,k )=T(I n J n,k-1 )+q0d z / K-Ad z 2 / 2K;

[0018] If the target sub-layer is metamorphic rock and igneous rock, the preset temperature calculation formula for this sub-layer is:

[0019]

[0020] A(I n J n,k ) = Aexp(-z / D);

[0021] Among them, T(I n J n,k ) is the temperature of the kth sublayer in the nth layer corresponding to the depth, T(In J n,0 )=T(I n- 1J n-1,k ), the top interface temperature of the nth layer is equal to the bottom interface temperature of the n-1th layer, T(0) = T(I1J 1,0 )=T0, T0 is the average surface temperature, K is the thermal conductivity of rock, A is the heat generation rate of rock, q0 is the surface heat flow value, D is the thickness of the radioactive heat-generating element enriched layer, d z is the thickness of the sublayer, z is the depth from the surface, I n J n,k It is the kth sublayer within the nth layer.

[0022] In a possible implementation, the rock heat generation rate A is calculated as follows:

[0023] For the sedimentary cover, the rock heat generation rate A is:

[0024] A=0.01ρ(9.52C U +2.56C Th +3.48C K );

[0025] For a stratum at a predetermined depth below the sedimentary cover, the rock heat generation rate A is:

[0026] A(z) = A0exp(-z / D);

[0027] Where ρ is the rock density (g / cm 3 );C U , C Th and C K are the contents of radioactive elements uranium, thorium and potassium respectively, A0 is the heat generation rate of the sedimentary cover, z is the depth from the surface, and D is the thickness of the radioactive heat-generating element enriched layer.

[0028] In a possible implementation, based on the temperatures of all target sub-layers at different depths, a temperature field distribution map of a target research area is determined, including:

[0029] Based on the temperatures of all target sub-layers at different depths, draw geothermal profiles and geothermal contour maps at different depths;

[0030] The geothermal field of the target study area is constructed based on the geothermal profile and geothermal contour maps at different depths.

[0031] In a possible implementation, the geological parameter database is determined based on the geological conditions of the target research area, and the geological parameter database also includes the thickness of the radioactive heat-generating element enriched layer;

[0032] The surface heat flow values ​​are obtained after de-peaking;

[0033] For rock thermal conductivity: the thermal conductivity of unconsolidated loose and weakly consolidated sediments on the surface is 1.0-2.4W / mK; the thermal conductivity of Mesozoic sedimentary strata is 2.4-2.8W / mK; the thermal conductivity of Paleozoic and older sedimentary layers is 2.8-3.4W / mK, and the thermal conductivity of thin mudstone is 2.1-2.6W / mK;

[0034] For rock heat generation rate: in igneous rocks, the heat generation rate of acidic rocks is 7.0W / mK, and the heat generation rate of basic and ultrabasic rocks is 0-0.2W / mK; in sedimentary rocks, the heat generation rate of mudstone and shale is 1.5-2.4W / mK, and the heat generation rate of metamorphic rocks is 0.6-3.0W / mK;

[0035] Regarding the thickness of the radioactive heat-generating element enriched layer: the thickness of the radioactive heat-generating element enriched layer in the central stable zone is 10km, the thickness of the radioactive heat-generating element enriched layer in the eastern thinning zone is 8km, and the thickness of the radioactive heat-generating element enriched layer in the Qinghai-Tibet Plateau is 15-20km.

[0036] In a second aspect, an embodiment of the present invention provides a device for establishing a deep temperature field of geothermal resources, comprising:

[0037] A construction module is used to construct a geological model of the target study area; wherein the geological model is used to visualize the strata, fracture structures and lithology of the target study area;

[0038] A stratification module is used to divide the target research area into multiple continuous strata based on the geological model, and to divide each target stratum into multiple continuous sub-strata; wherein the target stratum is any stratum, and the lithology of each target stratum is the same;

[0039] A calculation module, used to use the surface temperature as the starting point of temperature calculation, and calculate the temperature of each sub-layer in turn based on various geological parameters in the geological parameter database and a preset temperature calculation formula; wherein the geological parameter database at least includes surface heat flow value, rock thermal conductivity, rock heat generation rate and sub-layer thickness;

[0040] The distribution determination module is used to determine the temperature field distribution map of the target study area based on the temperatures of all sub-layers at different depths.

[0041] In a third aspect, an embodiment of the present invention provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the processor implements the steps of the method described in the first aspect or any possible implementation manner of the first aspect.

[0042] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in the first aspect or any possible implementation method of the first aspect are implemented.

[0043] The method for establishing the deep temperature field of geothermal resources provided by the embodiment of the present invention constructs a geological model of the target study area in order to visualize the strata, fracture structures and lithology of the target study area. Based on the visualized geological model, the target study area can be divided into multiple continuous layers, and each target layer can be divided into multiple continuous sub-layers, wherein the lithology of each target layer is the same. Thus, the difference in lithology and the difference in geological parameters in the vertical direction can be taken into account, and the influence of vertical differences on temperature can be better reflected. When calculating the temperature, the surface temperature is used as the starting point of the temperature calculation. Based on the geological parameters in the geological parameter database and the preset temperature calculation formula, the temperature of each sub-layer is calculated in turn, and the temperature of each sub-layer can be calculated more accurately, and the vertical change of the ground temperature can be more accurately portrayed. Finally, based on the temperature of all sub-layers at different depths, the temperature field distribution map of the target study area can be determined, and the temperature field distribution map can more scientifically reflect the actual physical characteristics of the underground temperature, and provide more reliable technical support for the exploration, development and utilization of geothermal resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0045] Figure 1 It is a flow chart of the implementation of the method for establishing the deep temperature field of geothermal resources provided by the embodiment of the present invention;

[0046] Figure 2 It is a single survey line electromagnetic profile of a target research area provided by an embodiment of the present invention;

[0047] Figure 3 yes Figure 2 Corresponding lithological interpretation profile;

[0048] Figure 4 is a schematic diagram of hierarchical segmentation provided by an embodiment of the present invention;

[0049] Figure 5 is a schematic diagram of geothermal contour lines at different depths provided by an embodiment of the present invention;

[0050] Figure 6 is a schematic diagram of the geothermal field of the target research area provided by an embodiment of the present invention;

[0051] Figure 7 It is a structural schematic diagram of a device for establishing a deep temperature field of geothermal resources provided by an embodiment of the present invention;

[0052] Figure 8 is a schematic diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0053] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0054] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0055] As introduced in the background technology, direct measurement is the most accurate method for measuring temperature. However, for a large number of areas without drilling, deep temperature cannot be measured directly. At present, although there are also geothermal thermometers using geophysical detection, this method is usually assumed to be unchanged with changes in spatial position, resulting in the inability to accurately calculate the ground temperature.

[0056] The temperature distribution at different depths underground is the core parameter for evaluating the potential of geothermal resources. After research, the inventors found that the existing evaluation methods can hardly accurately reflect the complex characteristics of vertical differences in ground temperature through linear extrapolation alone, which limits the scientificity and accuracy of geothermal resource evaluation and cannot provide technical support for the exploration and development of geothermal resources.

[0057] In order to solve the problems of the prior art, the embodiments of the present invention provide a method, device, equipment and storage medium for establishing a deep temperature field of geothermal resources. The method for establishing a deep temperature field of geothermal resources provided by the embodiments of the present invention is first introduced below.

[0058] See also Figure 1 , which shows a flow chart of the method for establishing a deep temperature field of geothermal resources provided by an embodiment of the present invention, and is described in detail as follows:

[0059] S110. Construct a geological model of the target study area.

[0060] Among them, the geological model is used to visualize the strata, fault structures and lithology of the target study area.

[0061] In some embodiments, a geological model of the target study area may be constructed based on the zoned stratigraphic table, drilling measurement data, seismic detection data, and wide-area electromagnetic measurement results of the target study area.

[0062] Before constructing a geological model for the target research area, it is necessary to first understand the geological tectonic background of the area. The geological tectonic background mainly understands the formation, development and change of rocks and strata in the crust of the area, and can have a certain subjective understanding of the state of deep rocks, whether there are magma chambers, etc.

[0063] In addition, the use of geophysical methods to survey deep underground features should be based on the local zoning stratigraphic table. The zoning stratigraphic table usually contains information such as the stratigraphic sequence from bottom to top and the lithology description of each stratum. This information can be obtained by consulting materials such as regional geological records.

[0064] The geological structural background of the region can also be understood through the stratigraphic sequence revealed by analyzing the drilling data.

[0065] Wide-area electromagnetic survey is an artificial source frequency domain electromagnetic sounding method. The comprehensive geological interpretation of wide-area electromagnetic profiles is mainly based on the electrical inversion of resistivity sections, and uses physical property data as a bridge, so that a geological-geophysical model can be systematically established. Figure 2 The figure shows the electromagnetic profile of a single survey line obtained by wide-area electromagnetic survey of a target research area. Figure 3 Based on Figure 2 The lithology interpretation profile corresponding to the profile of Figure 3 Different colors represent different rock types.

[0066] Based on the zoned stratigraphic table, drilling measured data, seismic detection data, and wide-area electromagnetic measurement results of the target study area, all data are integrated to ensure the consistency and accuracy of the data, and then stratigraphic division, lithology identification, and structural analysis can be performed. Through three-dimensional modeling technology, the spatial distribution of strata, fault structures, and lithology can be visualized to determine the spatial distribution of the target study area. Ultimately, the established geological model can fully reflect the geological characteristics of the target study area.

[0067] S120. Based on the geological model, the target study area is divided into a plurality of continuous layers, and each target layer is divided into a plurality of continuous sub-layers.

[0068] The target layer is any layer, and the lithology of each target layer is the same.

[0069] At present, conventional methods for calculating ground temperature are simply to use linear extrapolation to directly calculate. However, the inventors found that the linear extrapolation method is difficult to accurately reflect the complex characteristics of vertical differences in ground temperature, resulting in inaccurate temperature calculation. In order to improve the accuracy of ground temperature calculation, the present invention takes into account the differences in lithology and geological parameters in the vertical direction, and overcomes the limitations of the simple linear extrapolation method through a layered and segmented modeling method, which can better reflect the impact of vertical differences on temperature.

[0070] In some embodiments, the target research area can be divided into a plurality of continuous layers based on the geological model, and the thermophysical parameters of each layer are different. The thermophysical parameters include thermal conductivity and heat generation rate.

[0071] The stratification is based on the lithological changes in the geological section, such as Figure 4 As shown in the figure, the target research area is divided into several different layers, which are marked as I1, I2, I3…I n ,I n+1 Each layer represents a lithological unit with a single thermophysical property parameter.

[0072] After stratifying the target study area based on the lithological units of thermophysical parameters, in order to calculate the ground temperature more accurately, each layer needs to be segmented and each layer is divided into multiple sub-layers. The thickness of the sub-layer can be set according to the preset accuracy requirements. It should be noted that in the present invention, each layer is divided into multiple sub-layers of the same thickness, which is called segmentation. Figure 4 As shown in , the segmentation points in the n-1 layer are denoted by J n-1,0 , J n-1,1 , J n-1,2 …J n-1,k-1 , J n-1,k , where J n-1,0 is the top interface of this layer, J n-1,k is the bottom interface of this layer.

[0073] S130, taking the surface temperature as the starting point of temperature calculation, and calculating the temperature of each sub-layer in turn based on various geological parameters in the geological parameter database and a preset temperature calculation formula.

[0074] The geological parameter database includes at least surface heat flow value, rock thermal conductivity, rock heat generation rate and sub-layer thickness.

[0075] If the numerical values ​​of conventional geological parameters are directly applied to the preset temperature calculation formula, the numerical values ​​of geological parameters will be different due to the different geological conditions. Therefore, it is necessary to correct the numerical values ​​of various geological parameters in the geological parameter database based on the geological model of the target study area to adapt to the target study area, thereby improving the accuracy of subsequent calculations.

[0076] In order to avoid the influence of thermal effects of groundwater recharge and discharge, the surface heat flow value needs to be de-peaked, that is, the maximum value is 140mW / m 2 , the minimum value is 40mW / m 2 .

[0077] For rock thermal conductivity: the thermal conductivity of the surface unconsolidated loose-weakly consolidated sediments is 1.0-2.4W / mK; the thermal conductivity of the Mesozoic sedimentary strata is 2.4-2.8W / mK; the thermal conductivity of the Paleozoic and older sedimentary layers is 2.8-3.4W / mK, and the thermal conductivity of thin mudstone is 2.1-2.6W / mK.

[0078] Regarding the heat generation rate of rocks: in igneous rocks, the heat generation rate of acidic rocks is 7.0W / mK, and the heat generation rate of basic and ultrabasic rocks is 0-0.2W / mK; in sedimentary rocks, the heat generation rate of mudstone and shale is 1.5-2.4W / mK, and the heat generation rate of metamorphic rocks is 0.6-3.0W / mK.

[0079] It should be noted that the above are the numerical ranges of these parameters, and appropriate values ​​can be selected according to the area to be studied when using them.

[0080] Regarding the thickness of the radioactive heat-generating element enriched layer: the thickness of the radioactive heat-generating element enriched layer in the central stable zone is 10km, the thickness of the radioactive heat-generating element enriched layer in the eastern thinning zone is 8km, and the thickness of the radioactive heat-generating element enriched layer in the Qinghai-Tibet Plateau is 15-20km.

[0081] The heat generation rate A of rocks can be calculated using a hierarchical model. Rock samples of shallow sedimentary strata and crust can be obtained from boreholes. The heat generation rate and thermal conductivity of the rocks are generally measured using the actual values ​​of the samples. Therefore, for the shallow sedimentary cover layer on the surface, the uranium, thorium and potassium contents are tested through systematic sampling, and the formula A = 0.01ρ (9.52C U +2.56C Th +3.48C K ) to calculate the corresponding heat generation rate. Where ρ is the rock density (g / cm 3 );C U , C Th and C K They are the contents of radioactive elements uranium, thorium and potassium respectively.

[0082] For the relatively deep crust below the sedimentary cover, the heat generation rate of the rock is affected by the radioactive heat generating elements and decays exponentially with depth, following the depth exponential model, which can be calculated by the formula: A(z) = A0exp(-z / D). For the deeper crust and lithospheric mantle, it is estimated based on the seismic wave velocity data and crustal composition research results in the study area. A0 is the heat generation rate of the sedimentary cover, z is the depth, and D is the thickness of the radioactive heat generating element enriched layer.

[0083] The thermal conductivity K of rock can be experimentally measured using thermal conductivity testing instruments, TCS thermal conductivity scanning instruments, THB, optical scanning measurements, etc. It can also be corrected and calculated for the public limited thermal conductivity of rock. The formula is as follows.

[0084] The sedimentary rock pressure correction formula is:

[0085]

[0086] λ lab is the thermal conductivity at constant pressure of 0, P is the assumed in-situ pressure, in MPa. This formula can be applied to laboratory thermal conductivities between 1.5 and 5.0 W / (m·K).

[0087] The temperature correction formulas for sedimentary rocks include the SA equation, the SO equation, and the VS equation.

[0088] The correction formula for sedimentary rock saturation is:

[0089] λ cor =λ dry ·(λ w / λ a ) ω ;

[0090]

[0091] Among them, this formula is obtained by fitting the geometric mean model, and its result has a good fit with the experimental test value. The calculation formula is as follows:

[0092]

[0093] λ dry , cor are the measured dry rock thermal conductivity and the water-saturated corrected thermal conductivity, respectively; m , w , a are the thermal conductivity of rock matrix, the thermal conductivity of water and the thermal conductivity of air, respectively. w and λ a The values ​​are 0.600W / (m·K) and 0.026W / (m·K) respectively; is the porosity of rock, unit: %; ω is the water content of rock, unit: %.

[0094] In S120, stratification and segmentation have been performed, and the subsequent calculation of ground temperature can be performed based on the results of stratification and segmentation.

[0095] When calculating the temperature, the surface temperature is used as the starting point for the entire ground temperature calculation and is defined as: T(z) = T(0) = T(I1J 1,0 )=T0, T0 is the average surface temperature.

[0096] For the temperature relationship between the layers:

[0097] For the interface between two adjacent layers, maintain temperature continuity: T(I n J n,0 )=T(I n-1 J n-1,k ), that is, the top interface temperature of the nth layer is equal to the bottom interface temperature of the n-1th layer.

[0098] Starting from the surface, the temperature of each layer is calculated layer by layer, and for each layer, the temperature is calculated segmentally according to the sub-layers.

[0099] For each layer I n :

[0100] First, we need to determine the temperature T(I n J n,0 ).

[0101] Then, based on the thermophysical property parameters of the layer and selecting an appropriate preset temperature calculation formula, the temperature of each sub-layer can be calculated in turn.

[0102] Finally, calculate the interface temperature T(I n J n,k ).

[0103] If the target sub-layer is sedimentary rock, the temperature calculation formula for this sub-layer is:

[0104] T(I n J n,k )=T(I n J n,k-1 )+q0d z / K-Ad z 2 / 2K;

[0105] If the target sub-layer is metamorphic rock and igneous rock, the temperature calculation formula of this sub-layer is:

[0106]

[0107] A(In J n,k ) = Aexp(-z / D);

[0108] Among them, T(I n J n,k ) is the temperature of the kth sublayer in the nth layer corresponding to the depth, T(I n J n,0 )=T(I n- 1J n-1,k ), the top interface temperature of the nth layer is equal to the bottom interface temperature of the n-1th layer, T(0) = T(I1J 1,0 )=T0, T0 is the average surface temperature, K is the thermal conductivity of rock, A is the heat generation rate of rock, q0 is the surface heat flow value, D is the thickness of the radioactive heat-generating element enriched layer, d z is the thickness of the sublayer, z is the depth from the surface, I n J n,k It is the kth sublayer within the nth layer.

[0109] It should be noted that each sub-layer needs to be strictly limited to its corresponding layer. For thinner strata, the layer may not be divided into multiple sub-layers. However, for thicker strata, the layer needs to be divided into multiple sub-layers for detailed calculation.

[0110] In addition, when calculating temperature, the geological parameters of each layer or sub-layer may have different values. Changes in these values ​​will affect the results of the temperature calculation, thereby enabling the present invention to better reflect the complexity of vertical differences in geothermal temperature and better reflect the actual physical characteristics of the underground temperature field.

[0111] The following is an example of stratification and segmentation of a well in a certain area:

[0112] The average surface temperature T0 is 14°C, and the surface heat flow value q0 is 91mW / m 2 ,

[0113]

[0114]

[0115] S140. Determine a temperature field distribution map of the target research area based on the temperatures of all sub-layers at different depths.

[0116] In this embodiment, first, based on the temperatures of all target sub-layers at different depths, a geothermal profile and geothermal contour maps at different depths can be drawn. Figure 5 The figure shows the geothermal contour map drawn based on the calculated temperature results. Then, based on the geothermal profile and geothermal contour maps at different depths, the geothermal field of the target study area is constructed. Figure 6 Shown is the geothermal field of the constructed target study area.

[0117] The method for establishing the deep temperature field of geothermal resources provided by the embodiment of the present invention constructs a geological model of the target study area in order to visualize the strata, fracture structures and lithology of the target study area. Based on the visualized geological model, the target study area can be divided into multiple continuous layers, and each target layer can be divided into multiple continuous sub-layers, wherein the lithology of each target layer is the same. Thus, the difference in lithology and the difference in geological parameters in the vertical direction can be taken into account, and the influence of vertical differences on temperature can be better reflected. When calculating the temperature, the surface temperature is used as the starting point of the temperature calculation. Based on the geological parameters in the geological parameter database and the preset temperature calculation formula, the temperature of each sub-layer is calculated in turn, and the temperature of each sub-layer can be calculated more accurately, and the vertical change of the ground temperature can be more accurately portrayed. Finally, based on the temperature of all sub-layers at different depths, the temperature field distribution map of the target study area can be determined, and the temperature field distribution map can more scientifically reflect the actual physical characteristics of the underground temperature, and provide more reliable technical support for the exploration, development and utilization of geothermal resources.

[0118] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0119] Based on the method for establishing a deep temperature field of geothermal resources provided in the above embodiment, the present invention also provides a specific implementation of a device for establishing a deep temperature field of geothermal resources applied to the method for establishing a deep temperature field of geothermal resources. Please refer to the following embodiment.

[0120] like Figure 7 As shown, a device 700 for establishing a deep temperature field of geothermal resources is provided, and the device comprises:

[0121] A construction module 710 is used to construct a geological model of the target study area; wherein the geological model is used to visualize the strata, fracture structures and lithology of the target study area;

[0122] The stratification module 720 is used to divide the target research area into a plurality of continuous strata based on the geological model, and divide each target strata into a plurality of continuous sub-strata; wherein the target strata is any strata, and the lithology of each target strata is the same;

[0123] The calculation module 730 is used to use the surface temperature as the starting point of temperature calculation, and calculate the temperature of each sub-layer in turn based on various geological parameters in the geological parameter database and a preset temperature calculation formula; wherein the geological parameter database at least includes the surface heat flow value, rock thermal conductivity, rock heat generation rate and sub-layer thickness;

[0124] The distribution determination module 740 is used to determine the temperature field distribution map of the target research area based on the temperatures of all sub-layers at different depths.

[0125] In a possible implementation, the stratification module 720 is used to divide the target research area into a plurality of continuous strata based on the geological model; wherein the thermophysical property parameters of each strata are different, and the thermophysical property parameters include thermal conductivity and heat generation rate;

[0126] Based on the thickness of the target layer and the preset accuracy, the target layer is divided into multiple sub-layers with the same thickness.

[0127] In a possible implementation, the construction module 710 is used to construct a geological model of the target study area based on the zoned stratigraphic table, drilling measured data, seismic detection data, and wide-area electromagnetic measurement results of the target study area.

[0128] In a possible implementation, the calculation module 730 is used to calculate the temperature of the sub-layer as follows:

[0129] T(I n J n,k )=T(I n J n,k-1 )+q0d z / K-Ad z 2 / 2K;

[0130] If the target sub-layer is metamorphic rock and igneous rock, the temperature calculation formula of the sub-layer is:

[0131]

[0132] A(I n J n,k ) = Aexp(-z / D);

[0133] Among them, T(I n J n,k ) is the temperature of the kth sublayer in the nth layer corresponding to the depth, T(I n J n,0 )=T(I n- 1J n-1,k ), the top interface temperature of the nth layer is equal to the bottom interface temperature of the n-1th layer, T(0) = T(I1J1,0 (=T0, T0 is the average surface temperature, K is the thermal conductivity of rock, A is the heat generation rate of rock, q0 is the surface heat flow value, D is the thickness of the radioactive heat-generating element enriched layer, d z is the thickness of the sublayer, z is the depth, I n J n,k It is the kth sublayer within the nth layer.

[0134] In a possible implementation, the rock heat generation rate A is calculated as follows:

[0135] For the sedimentary cover, the rock heat generation rate A is:

[0136] A=0.01ρ(9.52C U +2.56C Th +3.48C K );

[0137] For a stratum at a predetermined depth below the sedimentary cover, the rock heat generation rate A is:

[0138] A(z) = A0exp(-z / D);

[0139] Where ρ is the rock density (g / cm 3 );C U , C Th and C K are the contents of radioactive elements uranium, thorium and potassium respectively, A0 is the heat generation rate of the sedimentary cover, z is the depth, and D is the thickness of the radioactive heat-generating element enriched layer.

[0140] In a possible implementation, the distribution module 740 is configured to draw a geothermal profile and geothermal contour maps at different depths based on the temperatures of all target sublayers at different depths;

[0141] The geothermal field of the target study area is constructed based on the geothermal profile and geothermal contour maps at different depths.

[0142] In a possible implementation, the geological parameter database is determined based on the geological conditions of the target research area, and the geological parameter database also includes the thickness of the radioactive heat-generating element enriched layer;

[0143] The surface heat flow values ​​are obtained after de-peaking;

[0144] For rock thermal conductivity: the thermal conductivity of unconsolidated loose and weakly consolidated sediments on the surface is 1.0-2.4W / mK; the thermal conductivity of Mesozoic sedimentary strata is 2.4-2.8W / mK; the thermal conductivity of Paleozoic and older sedimentary layers is 2.8-3.4W / mK, and the thermal conductivity of thin mudstone is 2.1-2.6W / mK;

[0145] For rock heat generation rate: in igneous rocks, the heat generation rate of acidic rocks is 7.0W / mK, and the heat generation rate of basic and ultrabasic rocks is 0-0.2W / mK; in sedimentary rocks, the heat generation rate of mudstone and shale is 1.5-2.4W / mK, and the heat generation rate of metamorphic rocks is 0.6-3.0W / mK;

[0146] Regarding the thickness of the radioactive heat-generating element enriched layer: the thickness of the radioactive heat-generating element enriched layer in the central stable zone is 10km, the thickness of the radioactive heat-generating element enriched layer in the eastern thinning zone is 8km, and the thickness of the radioactive heat-generating element enriched layer in the Qinghai-Tibet Plateau is 15-20km.

[0147] The device for establishing the deep temperature field of geothermal resources provided by the embodiment of the present invention constructs a geological model of the target study area in order to visualize the strata, fracture structures and lithology of the target study area. Based on the visualized geological model, the target study area can be divided into multiple continuous layers, and each target layer can be divided into multiple continuous sub-layers, wherein the lithology of each target layer is the same. Thus, the difference in lithology and the difference in geological parameters in the vertical direction can be taken into account, and the influence of vertical differences on temperature can be better reflected. When calculating the temperature, the surface temperature is used as the starting point of the temperature calculation. Based on the geological parameters in the geological parameter database and the preset temperature calculation formula, the temperature of each sub-layer is calculated in turn, and the temperature of each sub-layer can be calculated more accurately, and the vertical change of the ground temperature can be more accurately portrayed. Finally, based on the temperature of all sub-layers at different depths, the temperature field distribution map of the target study area can be determined, and the temperature field distribution map can more scientifically reflect the actual physical characteristics of the underground temperature, and provide more reliable technical support for the exploration, development and utilization of geothermal resources.

[0148] Figure 8 Schematic diagram of an electronic device provided by an embodiment of the present invention. Figure 8 As shown, the electronic device 8 of this embodiment includes: a processor 80, a memory 81, and a computer program 82 stored in the memory 81 and executable on the processor 80. When the processor 80 executes the computer program 82, the steps in the above-mentioned method for establishing the deep temperature field of geothermal resources are implemented, for example Figure 3 Alternatively, when the processor 80 executes the computer program 82, the functions of the modules in the above-mentioned device embodiments are realized, for example, Figure 7 Functions of modules 710 to 740 are shown.

[0149] Exemplarily, the computer program 82 may be divided into one or more modules, which are stored in the memory 81 and executed by the processor 80 to implement the present invention. The one or more modules may be a series of computer program instruction segments that can implement specific functions, and the instruction segments are used to describe the execution process of the computer program 82 in the electronic device 8. For example, the computer program 82 may be divided into Figure 7 Modules 710 to 740 are shown.

[0150] The electronic device 8 may include, but is not limited to, a processor 80 and a memory 81. Those skilled in the art will appreciate that Figure 8 It is only an example of the electronic device 8 and does not constitute a limitation of the electronic device 8. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices, network access devices, buses, etc.

[0151] The processor 80 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0152] The memory 81 may be an internal storage unit of the electronic device 8, such as a hard disk or memory of the electronic device 8. The memory 81 may also be an external storage device of the electronic device 8, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device 8. Further, the memory 81 may also include both an internal storage unit and an external storage device of the electronic device 8. The memory 81 is used to store the computer program and other programs and data required by the electronic device. The memory 81 may also be used to temporarily store data that has been output or is to be output.

[0153] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0154] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0155] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0156] In the embodiments provided by the present invention, it should be understood that the disclosed devices / electronic devices and methods can be implemented in other ways. For example, the device / electronic device embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0157] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0158] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0159] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned method embodiments for establishing the deep temperature field of geothermal resources can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium.

[0160] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for establishing a deep temperature field of geothermal resources, characterized in that: include: Constructing a geological model of the target study area; wherein the geological model is used to visualize the strata, fracture structures and lithology of the target study area; Based on the geological model, the target research area is divided into a plurality of continuous layers, and each target layer is divided into a plurality of continuous sub-layers; wherein the target layer is any layer, and the lithology of each target layer is the same; Taking the surface temperature as the starting point of temperature calculation, the temperature of each sub-layer is calculated in sequence based on various geological parameters in the geological parameter database and a preset temperature calculation formula; wherein the geological parameter database includes at least the surface heat flow value, rock thermal conductivity, rock heat generation rate and sub-layer thickness; Determine the temperature field distribution map of the target research area based on the temperatures of all sub-layers at different depths; If the target sub-layer is sedimentary rock, the preset temperature calculation formula for this sub-layer is: T(I n J n,k )=T(I n J n,k-1 )+q0d z / K-Ad z 2 / 2K; If the target sub-layer is metamorphic rock and igneous rock, the preset temperature calculation formula of the sub-layer is: A(I n J n,k )=Aexp(-z / D); Among them, T(I n J n,k ) is the temperature of the kth sublayer in the nth layer corresponding to the depth, T(I n J n,0 )=T(I n-1 J n-1,k ), the top interface temperature of the nth layer is equal to the bottom interface temperature of the n-1th layer, T(0) = T(I1J 1,0 )=T0, T0 is the average surface temperature, K is the thermal conductivity of rock, A is the heat generation rate of rock, q0 is the surface heat flow value, D is the thickness of the radioactive heat-generating element enriched layer, d z is the thickness of the sublayer, z is the depth from the surface, I n J n,k It is the kth sublayer within the nth layer.

2. The method of establishing as claimed in claim 1, characterized in that Based on the geological model, the target research area is divided into a plurality of continuous layers, and each target layer is divided into a plurality of continuous sub-layers, including: Based on the geological model, the target research area is divided into a plurality of continuous layers; wherein the thermophysical parameters of each layer are different, and the thermophysical parameters include thermal conductivity and heat generation rate; Based on the thickness of the target layer and a preset accuracy, the target layer is divided into a plurality of sub-layers with the same thickness.

3. The method of establishing as claimed in claim 1, characterized in that The construction of the geological model of the target research area includes: A geological model of the target study area is constructed based on the zoned stratigraphic table, drilling measurement data, seismic detection data and wide-area electromagnetic measurement results of the target study area.

4. The method of establishing as claimed in claim 1, characterized in that The calculation method of the rock heat generation rate A is: For the sedimentary cover, the rock heat generation rate A is: A=0.01ρ(9.52C U +2.56C Th +3.48C K ); For a stratum at a predetermined depth below the sedimentary cover, the rock heat generation rate A is: A(z) = A0exp(-z / D); Where ρ is the rock density (g / cm 3 );C U , C Th and C K are the contents of radioactive elements uranium, thorium and potassium respectively, A0 is the heat generation rate of the sedimentary cover, z is the depth from the surface, and D is the thickness of the radioactive heat-generating element enriched layer.

5. The method of establishing according to any one of claims 1 to 4, characterized in that: Determining the temperature field distribution map of the target research area based on the temperatures of all the target sub-layers at different depths includes: Based on the temperatures of all the target sub-layers at different depths, drawing geothermal profiles and geothermal contour maps at different depths; Based on the geothermal profile and geothermal contour maps at different depths, the geothermal field of the target research area is constructed.

6. The method of establishing according to any one of claims 1 to 4, characterized in that: The geological parameter database is determined based on the geological conditions of the target research area, and the geological parameter database also includes the thickness of the radioactive heat-generating element enriched layer; The surface heat flow value is obtained through de-peaking; For the thermal conductivity of the rock: the thermal conductivity of the surface unconsolidated loose-weakly consolidated sediments is 1.0-2.4W / mK; the thermal conductivity of the Mesozoic sedimentary strata is 2.4-2.8W / mK; the thermal conductivity of the Paleozoic and older sedimentary layers is 2.8-3.4W / mK, and the thermal conductivity of the thin mudstone is 2.1-2.6W / mK; Regarding the heat generation rate of the rock: in igneous rocks, the heat generation rate of acidic rocks is 7.0W / mK, and the heat generation rate of basic and ultrabasic rocks is 0-0.2W / mK; in sedimentary rocks, the heat generation rate of mudstone and shale is 1.5-2.4W / mK, and the heat generation rate of metamorphic rocks is 0.6-3.0W / mK; Regarding the thickness of the radioactive heat-generating element enriched layer: the thickness of the radioactive heat-generating element enriched layer in the central stable zone is 10km, the thickness of the radioactive heat-generating element enriched layer in the eastern thinning zone is 8km, and the thickness of the radioactive heat-generating element enriched layer in the Qinghai-Tibet Plateau is 15-20km.

7. A device for establishing a deep temperature field of geothermal resources, characterized in that: include: A construction module, used to construct a geological model of the target study area; wherein the geological model is used to visualize the strata, fracture structures and lithology of the target study area; A stratification module, for dividing the target research area into a plurality of continuous strata based on the geological model, and dividing each target strata into a plurality of continuous sub-strata; wherein the target strata is any strata, and the lithology of each target strata is the same; A calculation module, used to use the surface temperature as the starting point of temperature calculation, and calculate the temperature of each sub-layer in turn based on various geological parameters in the geological parameter database and a preset temperature calculation formula; wherein the geological parameter database at least includes surface heat flow value, rock thermal conductivity, rock heat generation rate and sub-layer thickness; A distribution determination module is used to determine a temperature field distribution map of the target research area based on the temperatures of all sub-layers at different depths; If the target sub-layer is sedimentary rock, the preset temperature calculation formula for this sub-layer is: T(I n J n,k )=T(I n J n,k-1 )+q0d z / K-Ad z 2 / 2K; If the target sub-layer is metamorphic rock and igneous rock, the preset temperature calculation formula of the sub-layer is: A(I n J n,k )=Aexp(-z / D); Among them, T(I n J n,k ) is the temperature of the kth sublayer in the nth layer corresponding to the depth, T(I n J n,0 )=T(I n-1 J n-1,k ), the top interface temperature of the nth layer is equal to the bottom interface temperature of the n-1th layer, T(0) = T(I1J 1,0 )=T0, T0 is the average surface temperature, K is the thermal conductivity of rock, A is the heat generation rate of rock, q0 is the surface heat flow value, D is the thickness of the radioactive heat-generating element enriched layer, d z is the thickness of the sublayer, z is the depth from the surface, I n J n,k It is the kth sublayer within the nth layer.

8. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to execute the method according to any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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