A multi-level progressive dynamic-static-flexible thermal reservoir comprehensive reconstruction method

Abstract

The application provides a kind of based on multilevel progressive heat storage comprehensive reconstruction method of dynamic-static-flexible, it is related to heat reservoir stimulation technical field.The method comprises the following steps: firstly, based on the original well logging data to establish rock mechanics profile model, obtain parameter set and calculate theoretical fracture pressure;Accordingly, the perforation horizon is optimized, high-energy blasting operation is carried out, and near-well low initiation pressure pretreatment zone is constructed by using shock wave and gas wedge effect;Then, guided by the pretreatment zone, large-displacement hydraulic fracturing is used to construct deep large-volume three-dimensional fracture network;Chemical stimulation medium is injected to form anti-closing fluid conductivity groove on the fracture wall;Finally, the production cycle is constructed, and the closed-loop optimization of operating parameters is realized based on wellhead flowback data.The application solves the problems of deep heat reservoir initiation difficulty, small sweep range and fracture closure difficulty through the synergistic effect of "dynamic" fracturing pressure reduction, "static" fracturing capacity expansion and "flexible" etching guide, and realizes the efficient development and long-term stable production of geothermal resources.

Description

Technical Field

[0001] This invention relates to the field of thermal reservoir production enhancement technology, and in particular to a multi-level progressive dynamic-static-flexible integrated thermal reservoir modification method. Background Technology

[0002] With the deepening development of geothermal energy, deep dry hot rocks and low-permeability geothermal reservoirs have become important replacement areas for the geothermal industry. Currently, the production enhancement and stimulation of such tight geothermal reservoirs mainly relies on hydraulic fracturing technology alone. This technology injects a large amount of fracturing fluid into the wellbore using a surface high-pressure pump set, using fluid pressure to cause the rock to fracture and extend, supplemented by proppant to keep the fractures open, thereby creating artificial heat exchange channels. In addition, some existing technologies also attempt to use a combination of acid fracturing, that is, adding acid during the hydraulic fracturing process to dissolve rock minerals.

[0003] To improve single-well productivity and thermal extraction efficiency, geothermal reservoir stimulation technology is gradually developing towards large-scale, high-displacement, and volumetric stimulation. The industry has increasingly recognized that relying solely on physical support or chemical dissolution is insufficient to maintain long-term fracture conductivity in the high-temperature, high-stress deep environment. Therefore, developing composite stimulation technologies, especially multi-field coupled production enhancement technologies that combine physical fracturing and chemical modification, has become a research hotspot and key focus in the field of deep geothermal engineering.

[0004] However, existing conventional hydraulic fracturing or single acid fracturing technologies still face severe challenges in deep, low-permeability geothermal reservoir applications. On the one hand, deep rock masses have high in-situ stress and high tensile strength, often resulting in extremely high fracturing pressures for conventional hydraulic fracturing. This leads to excessive loads on surface pumping equipment, sometimes even preventing effective fracturing initiation, and the resulting fracturing points are often singular, making it difficult to form complex fracture networks. On the other hand, single hydraulic fracturing in tight reservoirs tends to create straight, double-winged fractures, making it difficult to effectively connect with the existing natural fracture system in the formation. This results in insufficient geothermal reservoir stimulation volume and limited heat exchange area in the far-wellbore zone. Furthermore, under high-temperature, high-pressure creep conditions, fractures supported solely by proppant are prone to embedding into the rock mass or fracturing, leading to a rapid decline in conductivity. There is also a lack of long-term stimulation methods for fracture walls, and fluid channels are easily closed due to mineral precipitation or stress recovery. Summary of the Invention

[0005] In order to overcome the shortcomings of the existing technology, the purpose of this invention is to provide a multi-level progressive dynamic-static-flexible integrated transformation method for thermal reservoirs. This invention solves the problems of high initiation pressure of deep thermal reservoir rock mass leading to high construction difficulty, small fracture network coverage leading to low heat exchange efficiency, and poor fracture conductivity leading to rapid production decline in the existing technology.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A multi-level progressive dynamic-static-flexible integrated thermal storage modification method includes:

[0008] Obtain raw logging data for the target geothermal reservoir section;

[0009] Based on the elastic wave theory formula, a rock mechanical property profile model is established according to the original well logging data, and a set of rock mechanical parameters for the target depth is obtained according to the rock mechanical property profile model.

[0010] Based on the geostress calculation formula, the theoretical fracturing pressure value of conventional hydraulic fracturing is obtained according to the rock mechanics parameter set.

[0011] The perforation sites are determined within the target thermal reservoir section based on the set of rock mechanics parameters, and the blasting fracturing parameters are set based on the theoretical fracturing pressure value.

[0012] High-energy blasting based on the blasting fracturing parameters is performed at the perforation layer to obtain a near-wellbore low fracturing pressure pretreatment zone, wherein the near-wellbore low fracturing pressure pretreatment zone is a radially distributed well perimeter fractured area that is released from tangential stress constraint after being subjected to the blasting fracturing shock wave.

[0013] Based on the guiding effect of the near-wellbore low fracturing pressure pretreatment zone, a large-volume hydraulic fracturing operation is carried out using a surface high-pressure pump set to extend and expand the near-wellbore low fracturing pressure pretreatment zone into the deep formation, thereby constructing a deep large-volume three-dimensional fracture network. The deep large-volume three-dimensional fracture network is a volumetric seepage channel that connects the natural fracture system and links the near-wellbore and the distant well.

[0014] A chemical stimulating medium is injected into the deep, large-volume three-dimensional fracture network, and the fracture wall of the deep, large-volume three-dimensional fracture network is non-uniformly etched according to the slow reaction characteristics of the chemical stimulating medium to obtain fluid guiding trenches. The fluid guiding trenches are uneven, anti-closing fluid flow channels formed after the removal of mineral components by chemical stimulating dissolution.

[0015] The fluid diversion trench is used to construct a long-term geothermal fluid extraction circulation loop. During the operation of the long-term geothermal fluid extraction circulation loop, wellhead backflow data is collected in real time, and the injection flow rate and wellhead back pressure are dynamically adjusted based on the wellhead backflow data to achieve closed-loop optimization of the geothermal reservoir operating parameters.

[0016] The present invention discloses the following technical effects:

[0017] This invention provides a multi-level progressive dynamic-static-flexible integrated geothermal reservoir stimulation method. The method employs dynamic blasting to induce fracturing, creating a radial fracture zone around the wellbore, effectively relieving tangential stress constraints, significantly reducing rock mass fracturing pressure, and increasing fracturing paths. Static hydraulic fracturing guides deep fracture extension and activates the natural fracture system, constructing a large-volume three-dimensional fracture network connecting nearby and distant wells, significantly increasing the geothermal reservoir stimulation volume and heat exchange area. Combined with flexible chemical non-uniform etching, anti-clogging fluid-guiding channels are formed on the fracture walls, fundamentally solving the problem of decreased conductivity caused by fracture closure under high temperature and high pressure environments. This achieves efficient fracturing initiation, volumetric production enhancement, and long-term stable production in geothermal reservoir development. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart of a multi-level progressive dynamic-static-flexible thermal storage integrated renovation method provided in this embodiment of the invention;

[0020] Figure 2 This is a schematic diagram of the control logic for a mining cycle provided in an embodiment of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] like Figure 1 As shown, this invention provides a multi-level progressive dynamic-static-flexible integrated thermal storage modification method, including:

[0024] Step 100: Obtain the raw logging data for the target thermal reservoir section;

[0025] Step 200: Based on the elastic wave theory formula, establish a rock mechanical property profile model according to the original logging data, and obtain the rock mechanical parameter set at the target depth according to the rock mechanical property profile model;

[0026] Step 300: Based on the geostress calculation formula, obtain the theoretical fracturing pressure value of conventional hydraulic fracturing according to the rock mechanics parameter set;

[0027] Step 400: Determine the perforation zone within the target thermal reservoir section based on the rock mechanics parameter set, and set the blasting fracturing parameters based on the theoretical fracturing pressure value;

[0028] Step 500: Perform high-energy blasting operation based on the blasting fracturing parameters at the perforation layer to obtain a near-wellbore low fracturing pressure pretreatment zone, wherein the near-wellbore low fracturing pressure pretreatment zone is a radially distributed wellbore fractured area that has been released from tangential stress constraint after being subjected to the blasting fracturing shock wave.

[0029] Step 600: Based on the guiding effect of the flow path of the near-wellbore low fracturing pressure pretreatment zone, a large-volume hydraulic fracturing operation is carried out using a surface high-pressure pump set to extend and expand the near-wellbore low fracturing pressure pretreatment zone into the deep formation, thereby constructing a deep large-volume three-dimensional fracture network. The deep large-volume three-dimensional fracture network is a volumetric seepage channel that connects the natural fracture system and links the near-wellbore and the distant well.

[0030] Step 700: Inject a chemical stimulating medium into the deep, large-volume three-dimensional fracture network, and perform non-uniform etching on the fracture wall of the deep, large-volume three-dimensional fracture network according to the slow reaction characteristics of the chemical stimulating medium to obtain a fluid guiding trench. The fluid guiding trench is an uneven, anti-closing fluid flow channel formed after removing mineral components by chemical stimulating etching.

[0031] Step 800: Construct a long-term geothermal fluid extraction circulation loop using the fluid diversion trench. During the operation of the long-term geothermal fluid extraction circulation loop, collect wellhead backflow data in real time, and dynamically adjust the injection flow rate and wellhead back pressure based on the wellhead backflow data to achieve closed-loop optimization of geothermal reservoir operating parameters.

[0032] Furthermore, the specific implementation process of step 100 is as follows:

[0033] This embodiment first utilizes high-precision geophysical logging instruments to acquire in-situ data of the target geothermal reservoir section. Specifically, this embodiment uses either cable delivery or measurement-while-drilling (MWD) to lower a combined logging string integrating a multipole array sonic logging instrument, a lithology density logging instrument, and a natural gamma ray spectrometer into the wellbore to a predetermined depth. During the lifting or drilling process of the logging instruments, this embodiment continuously records the physical field signals varying along the wellbore depth direction at preset high-resolution sampling intervals, thereby acquiring raw logging data covering the entire target geothermal reservoir section.

[0034] Considering the high temperature and pressure characteristics and wellbore irregularities of deep geothermal reservoirs, this embodiment performs standardized environmental correction and depth alignment processing on the acquired raw logging data. This embodiment utilizes synchronously acquired caliper curves and mud performance parameters to perform wellbore enlargement correction and mud invasion correction on sonic transit time data and formation density data, eliminating interference from wellbore environmental factors on the measured values. Simultaneously, this embodiment uses a depth matching algorithm to eliminate depth hysteresis errors caused by differences in the positions of different sensors on the logging string, ensuring strict alignment of sonic transit time data, formation density data, and natural gamma data at every depth point.

[0035] The raw well logging data obtained in this embodiment provides the basic input parameters for subsequent rock mechanics modeling. Specifically, the sonic transit time data includes P-wave and S-wave transit time curves, used to characterize the elastic wave propagation characteristics and skeletal hardness of the formation rocks. The formation density data reflects the bulk density characteristics of the rocks; this embodiment uses this data to calculate the overlying strata pressure and vertical principal stress components. The natural gamma data reflects the content of naturally occurring radionuclides in the formation rocks; this embodiment uses this data to identify formation lithological boundaries and calculate the reservoir clay content index, thereby providing a quantitative basis for lithological correction of rock mechanics parameters.

[0036] Furthermore, the specific implementation process of step 200 is as follows:

[0037] This embodiment first calculates the dynamic parameters of the raw logging data obtained in step 100 based on the theory of elastic wave propagation in rock media. Specifically, this embodiment uses elastic wave theory formulas to convert the P-wave and S-wave transit times in the acoustic transit time data into P-wave velocities and S-wave velocities, respectively. Subsequently, this embodiment inputs the calculated P-wave and S-wave velocities and the formation density data at the synchronous depth into the dynamic elastic parameter calculation model, and calculates the dynamic elastic modulus curve and dynamic Poisson's ratio curve for the entire well section point by point. This process transforms the acoustic signal into a physical quantity characterizing the rock's ability to resist instantaneous elastic deformation, laying the foundation for subsequent static mechanical property analysis.

[0038] Considering that the dynamic parameters obtained from well logging are based on high-frequency acoustic micro-strain conditions, while the actual hydraulic fracturing process is a low-frequency, large-strain process, there are significant differences between the two. Therefore, this embodiment further introduces a lithology correction mechanism. This embodiment uses natural gamma data to calculate the clay content index of the target reservoir section, which reflects the relative abundance of clay minerals in the formation. Based on this clay content index, this embodiment retrieves or fits the corresponding lithology correction coefficient to correct the dynamic parameter deviations caused by rock heterogeneity and pore fluid influence, ensuring that the converted mechanical parameters better match the true mechanical response of the rock under quasi-static loading conditions.

[0039] This embodiment utilizes the lithology correction coefficient to perform dynamic-to-static conversion correction on the aforementioned dynamic elastic modulus curve and dynamic Poisson's ratio curve, generating static Young's modulus profiles and static Poisson's ratio profiles that can guide engineering design. Based on this, to evaluate the rock's resistance to tensile failure, this embodiment introduces the Griffith strength criterion, deriving a rock tensile strength profile distributed along well depth using the static Young's modulus profile. This embodiment performs depth alignment and data fusion on the generated static Young's modulus profile, static Poisson's ratio profile, and rock tensile strength profile to construct a rock mechanical property profile model reflecting the continuous variation of formation rock mechanical properties with depth.

[0040] Finally, this embodiment determines the target depth to be modified based on actual engineering needs and accurately locates the depth node corresponding to the target depth in the rock mechanical property profile model. This embodiment directly reads the static Young's modulus, static Poisson's ratio, and rock tensile strength values ​​at this depth node, and combines them to output a set of rock mechanical parameters for the target depth. This parameter set directly serves as the quantitative basis for subsequent calculations of theoretical fracture pressure, selection of perforation sites, and design of blasting parameters, realizing a logical closed loop from raw well logging data to executable engineering parameters.

[0041] Furthermore, the expression for the elastic wave theory formula is as follows:

[0042] ;

[0043] in, For the dynamic Young's modulus of rock; The dynamic Poisson's ratio of the rock; The formation density data; The longitudinal wave velocity is obtained by converting the acoustic time difference data. The transverse wave velocity is obtained by converting the acoustic time difference data. This is a unit conversion constant.

[0044] Specifically, this embodiment utilizes elastic wave theory formulas to achieve quantitative inversion of dynamic mechanical parameters of rocks. First, the acoustic transit time data in the original well logging data is reciprocally calculated, converting the slowness data (time per meter) into P-wave and S-wave velocities (meters per second), while simultaneously reading formation density data at the corresponding depth. Based on this, according to the principles of elastic dynamics, this embodiment calculates the dynamic Poisson's ratio of the rock, reflecting the ratio of lateral to axial deformation under instantaneous elastic wave loading, using the square ratio of P-wave and S-wave velocities. Simultaneously, combining the product of formation density data and the square of the S-wave velocity, and weighting this product using the P-wave / S-wave velocity ratio, the dynamic Young's modulus of the rock, reflecting its resistance to elastic deformation, is calculated. To ensure dimensional consistency in the calculation results, this embodiment introduces a unit conversion constant to align the density and velocity units used in the calculation with the final required pressure units (such as gigapascals), thereby obtaining a set of rock mechanical parameters that conforms to engineering application standards.

[0045] The following explanation uses an actual operation in a deep geothermal reservoir section as an example. Assume that at a specific depth point in this embodiment, the formation density data collected and converted by the logging instrument comes from the measured volumetric density of the formation rock, which is 2.65 grams per cubic centimeter, representing the density of the rock. The P-wave velocity, converted from sonic transit time logging data, is 4500 meters per second, reflecting the propagation speed of compression waves in the formation. The S-wave velocity, also converted from sonic transit time logging data, is 2600 meters per second, reflecting the propagation speed of shear waves in the formation. The unit conversion constant is set to 1 to maintain direct calculation using the International System of Units (SI). Based on these specific values, this embodiment calculates that the dynamic Poisson's ratio of the rock at this depth point is approximately 0.25, indicating a moderate lateral expansion trend of the rock under pressure. Simultaneously, the dynamic Young's modulus of the rock is calculated to be approximately 48 gigapascals, indicating that the rock at this location has high rigidity and resistance to deformation.

[0046] Furthermore, the specific implementation process of step 300 is as follows:

[0047] This embodiment first establishes the fundamental components of the three-dimensional stress field of the formation, namely the vertical principal stress and the formation pore pressure. This embodiment performs continuous depth integration along the well depth direction on the formation density data obtained in step 100, converting the cumulative gravity of the overlying rock into a vertical compaction load that increases with depth, thereby accurately quantifying the vertical principal stress components at the target depth. Simultaneously, this embodiment utilizes the response differences of acoustic transit time data under different compaction states, establishing a mapping relationship between acoustic transit time and fluid pressure through the Eaton method or other empirical formulas. This allows for the calculation of the formation pore pressure value supported by the fluid inside the rock pores at the target depth, providing a necessary pressure benchmark for subsequent effective stress calculations.

[0048] Based on this, this embodiment derives the horizontal principal stress state using the lateral deformation characteristics of rocks. This embodiment extracts the static Poisson's ratio parameter from the rock mechanics parameter set generated in step 200, and uses the geostress calculation formula to map the previously calculated vertical principal stress components and formation pore pressure values ​​into horizontal stress components. In this process, this embodiment fully considers the lateral compression caused by the Poisson effect and the additional tectonic stress generated by regional tectonic movements. Through coupled calculations, the maximum horizontal principal stress value parallel to the tectonic principal stress direction and the minimum horizontal principal stress value perpendicular to the tectonic principal stress direction are analyzed, thereby constructing a complete geostress profile for the target well section.

[0049] Finally, this embodiment constructs a fracturing initiation criterion model for conventional hydraulic fracturing based on the maximum tensile stress criterion to calculate the critical pressure threshold for tensile failure of the rock. This embodiment extracts the rock tensile strength parameter, characterizing the rock's resistance to tensile failure, from the rock mechanics parameter set. This parameter, along with the previously calculated maximum and minimum horizontal principal stress values ​​and formation pore pressure values, is substituted into the fracturing pressure calculation model. Through model calculations, this embodiment simulates the ultimate pressure required for the fluid pressure inside the wellbore to overcome the minimum tangential stress around the well and the tensile strength of the rock under conventional operating conditions without any preprocessing. This yields the theoretical fracturing pressure value for conventional hydraulic fracturing, which will serve as key benchmark data for subsequently setting the pressure reduction range during blasting.

[0050] Furthermore, the expression for the geostress calculation formula is as follows:

[0051] ;

[0052] Furthermore, the calculation expression for the rupture pressure calculation model is as follows:

[0053] ;

[0054] in, These are the vertical principal stress components; For target depth; This represents the formation density function that varies with depth. It is the acceleration due to gravity; This represents the minimum horizontal principal stress value. This represents the maximum horizontal principal stress value. The value of Poisson's ratio in the static Poisson's ratio profile; The pore pressure value of the formation; The effective stress coefficient; These are structural stress components; This refers to the theoretical fracturing pressure value of conventional hydraulic fracturing; The tensile strength of the rock is given.

[0055] Specifically, this embodiment utilizes the geostress calculation formula and the fracture pressure calculation model to achieve quantitative analysis of the formation stress state. First, through an integral algorithm, the product of the formation density function varying with depth and the gravitational acceleration is accumulated along the wellbore depth direction to calculate the vertical principal stress component at the target depth. This component characterizes the gravity compaction effect of the overlying strata. Subsequently, based on the elastic theory of porous media, this embodiment uses the effective stress coefficient to weight the formation pore pressure value, subtracts the fluid support effect from the vertical principal stress component to obtain the vertical effective stress, and constructs a lateral conversion coefficient using the Poisson's ratio value in the static Poisson's ratio profile to calculate the lateral component generated by the rock under gravity compression. Then, the tectonic stress component generated by regional tectonic movement is superimposed to analyze the maximum and minimum horizontal principal stress values ​​in the formation. Finally, based on the stress balance mechanism of the wellbore rock, this embodiment calculates the theoretical fracturing pressure value for conventional hydraulic fracturing by subtracting one time the maximum horizontal principal stress value from three times the minimum horizontal principal stress value, deducting the auxiliary support effect of formation pore pressure, and adding the tensile strength of the rock itself. This theoretical fracturing pressure value represents the ultimate fluid pressure required to induce tensile failure of the wellbore rock solely through hydraulic pressurization without any blasting pretreatment.

[0056] The following example illustrates the process using a specific operating depth in a deep granite geothermal reservoir. Assume the target depth is selected as 3500 meters; the gravitational acceleration is taken as the standard physical constant of 9.8 m / s²; the formation density function varying with depth, after averaging well logging data, has an equivalent value of 2.6 g / cm³, from which the vertical principal stress component is calculated to be approximately 91 MPa, derived from the total weight of the overlying strata; the formation pore pressure, determined through sonic logging inversion, is 35 MPa, derived from the hydrostatic pressure column of the formation fluid; the effective stress coefficient is taken as 0.8 based on the rock's density; the Poisson's ratio in the static Poisson's ratio profile is measured as 0.25, reflecting the rock's lateral deformation capacity; and the tectonic stress component is taken as 5 MPa based on regional geological exploration data. Based on the above fundamental data, the minimum horizontal principal stress is calculated to be approximately 58 MPa, and the maximum horizontal principal stress is approximately 68 MPa. Further analysis of the rock tensile strength obtained from rock mechanics experiments showed it to be 8 MPa. Substituting this into the model, the theoretical fracturing pressure value for conventional hydraulic fracturing was calculated to be approximately 79 MPa. This value indicates that without blasting pretreatment, the ground pumping pressure must exceed 79 MPa to induce fracturing in the formation.

[0057] Furthermore, the specific implementation process of step 400 is as follows:

[0058] This embodiment first quantitatively assesses the fracturing capability of the entire well section based on a set of rock mechanics parameters to accurately pinpoint the advantageous perforation sites. Specifically, this embodiment extracts static Young's modulus and static Poisson's ratio data distributed along the well depth, and performs extreme value normalization on them to eliminate dimensional differences. This embodiment substitutes the normalized Young's modulus and Poisson's ratio into a preset rock brittleness evaluation model to calculate a brittleness index curve reflecting the ease of rock fracturing. Based on this, this embodiment introduces a rock tensile strength profile and uses a two-factor weighted coupling analysis method to search for depth intervals that simultaneously satisfy high brittleness index and low tensile strength values ​​throughout the entire well section. This embodiment determines this depth interval as the preferred region most likely to form a complex fracture network through physical impact and identifies it as the perforation site for subsequent operations.

[0059] After determining the construction location, this embodiment designs the peak target of the blasting pressure based on the energy matching principle. This embodiment obtains the theoretical fracturing pressure value of conventional hydraulic fracturing calculated in step 300, which represents the fracturing initiation threshold under quasi-static loading. To achieve dynamic fracturing, this embodiment sets an overpressure coefficient greater than 1 based on the effective fracturing criterion. This overpressure coefficient characterizes the multiplication factor of the dynamic impact load relative to the static fracturing pressure. This embodiment calculates the product of the theoretical fracturing pressure value and this overpressure coefficient to obtain the target peak blasting pressure value that can instantly break through the wellbore stress circle and generate multiple fractures, thereby ensuring that the blasting energy can effectively create fractures without causing permanent damage to the wellbore structure.

[0060] Finally, this embodiment converts the pressure target into executable charge parameters based on the physical equation of state. This embodiment obtains the wellbore geometry parameters at the perforation site, including the casing inner diameter and the length of the treatment section, to determine the effective pressurized volume for the blasting operation. This embodiment utilizes the combustion equation of state for the high-energy gas generator, using the aforementioned peak blast pressure target value and effective pressurized volume as boundary conditions, to deduce the required charge amount of the high-energy gas generator. Simultaneously, this embodiment determines the optimal pressure rise time based on the dynamic response characteristics of the rock, and then calculates the corresponding combustion loading rate. This embodiment encapsulates the determined peak blast pressure target value, charge amount, and combustion loading rate to generate blasting fracturing parameters to guide on-site operations.

[0061] Furthermore, the expression for the rock brittleness evaluation model is as follows:

[0062] ;

[0063] in, The brittleness index value in the brittleness index curve; The Young's modulus in the set of rock mechanical parameters; This is the normalized Young's modulus; and These represent the maximum and minimum values ​​of Young's modulus within the target well section, respectively. The normalized Poisson's ratio; and These represent the maximum and minimum Poisson's ratios within the target well section, respectively.

[0064] Specifically, this embodiment utilizes a rock brittleness evaluation model to quantitatively characterize the ease of rock fracturing in formations. Specifically, since Young's modulus and Poisson's ratio have different physical dimensions and significantly different numerical ranges, this embodiment first performs statistical analysis on the rock mechanical parameters within the target well section, selecting the maximum and minimum values ​​of Young's modulus and Poisson's ratio within that section as boundary conditions for normalization. Subsequently, this embodiment performs dimensionless normalization: for Young's modulus, the difference between the Young's modulus at the current depth and the minimum value is calculated and divided by the extreme difference of Young's modulus across the entire well section to obtain the normalized Young's modulus, which reflects the positive contribution of rock stiffness to brittleness; for Poisson's ratio, considering that rocks with low Poisson's ratios are more conducive to forming complex fracture networks, this embodiment uses reverse normalization logic, calculating the difference between the maximum Poisson's ratio and the Poisson's ratio at the current depth and dividing by the extreme difference of Poisson's ratio across the entire well section to obtain the normalized Poisson's ratio. Finally, in this embodiment, the arithmetic mean of the normalized Young's modulus and the normalized Poisson's ratio is taken and converted into a percentage value to obtain the brittleness index value in the brittleness index curve. The higher the index value, the more easily the rock undergoes brittle fracture rather than plastic deformation under external loads, thus making it more suitable as a fracturing layer.

[0065] The following example illustrates the parameter values ​​at a specific depth point. Assume that, according to this embodiment, the maximum Young's modulus within the target well section originates from the densest layer (60 GPa) and the minimum from a fractured layer (20 GPa); the maximum Poisson's ratio originates from a high-clay layer (0.35) and the minimum from a pure quartz layer (0.15). If, at the current depth point, the rock mechanics parameter set obtained in step 200 shows a Young's modulus of 50 GPa and a Poisson's ratio of 0.25, this embodiment first calculates the normalized Young's modulus by dividing the difference between 50 and 20 by 40, resulting in 0.75; simultaneously, it calculates the normalized Poisson's ratio by dividing the difference between 0.35 and 0.25 by 0.2, resulting in 0.5. Finally, in this embodiment, the brittleness index value at that depth point is calculated to be 62.5 by adding 0.75 and 0.5, dividing by 2, and then multiplying by 100. This value quantifies the potential of the rock at that location to be suitable for volumetric fracturing, and is derived from a comprehensive evaluation of the rock's inherent elastic properties.

[0066] Furthermore, the specific implementation process of step 500 is as follows:

[0067] This embodiment first performs a high-precision device delivery and positioning operation. The shaped charge fracturing device, pre-loaded with a specific ratio of high-energy gas generator, is lowered into the wellbore via cable or tubing and precisely aligned with the center depth of the perforation zone determined in step 400. After confirming the device's positioning, this embodiment controls the ignition sequence according to the blasting fracturing parameters set in step 400, particularly strictly adhering to the calculated combustion loading rate. This embodiment sends an ignition command through the ground control system to ignite the high-energy gas generator, causing a violent chemical reaction within milliseconds. This instantaneously releases enormous chemical energy within the confined wellbore space, generating a transient high-pressure shock wave with a specific pressure peak, followed by rapidly expanding high-temperature, high-pressure gaseous products.

[0068] With the instantaneous release of energy, this embodiment utilizes transient high-pressure shock waves as the first-stage rock-breaking force, directly acting on the wellbore rock with an impact force exceeding the dynamic compressive strength of the rock. This dynamic impact causes high-strain-rate compressive failure in the rock medium surrounding the wellbore, thereby creating a high-density fractured zone in the surrounding rock mass. Subsequently, this embodiment utilizes the generated high-temperature, high-pressure gas as the second-stage fracture-expanding force, leveraging the gas's wedge-like expansion effect. This high-temperature, high-pressure gas rapidly penetrates the microcrack network within the fractured zone, utilizing the gas's fluid splitting effect to drive the microcracks to rapidly expand and penetrate radially deep, thereby forcibly tearing multiple radially distributed macroscopic main fractures in the surrounding rock mass.

[0069] This embodiment achieves the reconstruction of the wellbore stress field through the opening effect of the aforementioned radial main fractures. Specifically, the formation of radial main fractures interrupts the original continuous circumferential structure of the wellbore rock, effectively disrupting the original circumferential closed stress circle of the wellbore rock mass, thereby relieving the tangential stress constraint of the formation on the wellbore. This physical change significantly reduces the fracturing resistance required for subsequent fluid entry into the formation, resulting in a rock fracturing pressure in this area that is significantly lower than the original formation fracturing pressure. This embodiment defines this wellbore fractured area, which has undergone shock wave fracturing and stress release treatment and possesses radial fracture morphology and low fracturing pressure characteristics, as the near-wellbore low fracturing pressure pretreatment zone, providing an advantageous channel for the successful initiation of subsequent high-volume hydraulic fracturing.

[0070] Furthermore, the specific implementation process of step 600 is as follows:

[0071] In this embodiment, a high-power pump unit is rigidly connected to the wellhead equipment via a surface high-pressure manifold, and the pump unit is started to inject fluid into the wellbore using a preset high-flow-rate injection program. In the initial stage of fracturing, low-viscosity slickwater is selected as the pre-fluid, utilizing its low frictional characteristics to quickly transmit pressure to the bottom of the well. This embodiment utilizes the near-wellbore low fracture initiation pressure pretreatment zone formed in step 500 as a dominant fluid inlet channel, allowing high-pressure fluid to preferentially enter and accumulate within the radial main fractures. Under continuous net fluid pressure, this embodiment forces these radial main fractures, which originally only opened in the near-wellbore zone, to break through the in-situ stress limitations and rapidly extend along the direction of the maximum horizontal principal stress into the deeper and more distant parts of the formation, thereby constructing several long-distance extended main fracture channels in the tight thermal reservoir.

[0072] After the main fracture channel is formed, this embodiment switches the injected fluid to a gel system carrying high-strength proppant or a mixed fracturing fluid system, maintaining a high pump pressure injection state. During this process, this embodiment utilizes the filtration effect of the high-pressure fluid at the main fracture wall to allow some fracturing fluid to seep into the rock matrix and microfractures on both sides of the main fracture, resulting in a local increase in rock pore pressure. This change in pore pressure effectively reduces the effective stress of the rock, thereby inducing the activation of the natural fracture system distributed on both sides of the main fracture. Through this hydraulic-mechanical coupling effect, this embodiment promotes the shear slip or tensile opening of closed natural fractures, thereby generating a large number of non-planar multi-level secondary fractures around the main fracture.

[0073] Finally, this embodiment precisely controls the pump injection rate and sand ratio to ensure that the multi-stage secondary fractures and the main fracture channels are spatially interwoven, connected, and interconnected, forming a complex, tree-like network structure. Simultaneously, this embodiment utilizes the sand-carrying capacity of the adhesive system to progressively deliver and fill the proppant from the main fracture channels into the deep part of the network structure and the ends of the secondary fractures. This embodiment utilizes the proppant's supporting effect to prevent fracture closure after pump shutdown, thereby solidifying within the reservoir to form a volumetric seepage channel that connects the natural fracture system and links the near-wellbore and far-wellbore zones, thus constructing the deep, large-volume three-dimensional fracture network.

[0074] Furthermore, the specific implementation process of step 700 is as follows:

[0075] This embodiment first refines the formulation system of the chemically stimulated medium based on the mineral composition characteristics of the reservoir rock and the formation temperature gradient. This embodiment selects a high-temperature slow-reacting acid with high stability in high-temperature environments and a controllable reaction rate as the main agent, and combines it with a specific proportion of viscosity control agent to adjust the fluid rheology. During the injection stage, this embodiment strictly controls the discharge rate of the surface pump unit to ensure that the bottom hole fluid pressure is always lower than the re-fracture pressure of the formation rock. This embodiment, through this matrix acidizing or closed-loop acid fracturing injection mode, forces the chemically stimulated medium to uniformly enter the deep, large-volume three-dimensional fracture network constructed in step 600, relying on its own penetration and flow capabilities, avoiding the generation of ineffective new fractures or damage to the existing fracture network structure due to excessive pressure.

[0076] Upon entering the fracture network, this embodiment utilizes the special rheological properties imparted to the fluid by a viscosity control agent to induce hydrodynamic instability within the narrow fracture width. Specifically, this embodiment leverages the viscosity difference between high-viscosity acid and low-viscosity formation fluid or pre-fluid to induce viscous fingering on the flow front of the chemically stimulated medium. This physical phenomenon causes the acid to fail to propel uniformly in a piston-like manner, instead splitting into several faster-flowing finger-like fluids, forming a non-uniformly distributed dominant flow fingerprint path on the fracture plane. This embodiment precisely controls the wavelength and amplitude of fingering by adjusting the viscosity ratio and acid injection rate, thereby planning the main reaction trajectory of the acid at the microscale.

[0077] Finally, this embodiment utilizes a high-temperature, slow-moving acid to undergo a non-uniform chemical reaction along the dominant flow fingerprint path, constructing a self-supporting flow-guiding structure. This embodiment utilizes the dissolving reaction between the acid and rock minerals to deeply dissolve the rock surface along the acid flow fingerprint path, etching continuous and deep-set fluid flow channels. In areas unaffected by the acid or with low acid concentrations, the rock skeleton is preserved intact, forming raised support pillars. This embodiment defines this uneven structure, composed of continuous grooves and dispersed support pillars, as a fluid-guiding channel. The support pillars support the fracture walls under closure pressure, while the grooves serve as high-speed channels for geothermal fluids. After the reaction, this embodiment immediately pumps in a post-displacement fluid to completely discharge the waste acid and mineral residue generated during the reaction from the wellbore, preventing secondary precipitation and channel blockage.

[0078] Furthermore, the specific implementation process of step 800 is as follows:

[0079] This embodiment first constructs a physically closed fluid circulation hardware facility on the surface, connecting the fluid diversion trench constructed downhole to the energy production process. Specifically, this embodiment uses an insulated delivery pipeline to create an airtight connection between the production wellhead and the inlet of the surface heat exchange system. After extracting heat energy from the geothermal fluid, the cooled tailwater is fed back from the outlet of the surface heat exchange system to the inlet of the high-pressure injection equipment, thus forming a long-term geothermal fluid extraction circulation loop connecting the underground thermal reservoir and the surface facilities. Based on this, this embodiment deploys a high-density monitoring sensor array at the fluid outlet of the production well, i.e., before the inlet of the surface heat exchange system, including high-precision temperature transmitters, pressure transmitters, and turbine flow meters. This embodiment utilizes this monitoring sensor array to collect wellhead backflow data reflecting the thermal reservoir's production status in real time at a millisecond-level sampling frequency, focusing on monitoring outlet temperature fluctuations, outlet pressure stability, and the continuity of instantaneous flow rate.

[0080] After obtaining the raw monitoring data, this embodiment utilizes an edge computing unit to perform real-time feature extraction and secondary calculations to quantify the operational health of the thermal reservoir. This embodiment performs time-series correlation analysis on the outlet temperature and instantaneous flow rate, calculating the temperature decay slope per unit time or unit cumulative production, defining it as the thermal breakthrough rate index, to determine the risk of premature cold water leakage to the production well along high-conductivity fractures. Simultaneously, this embodiment acquires injection pressure data at the injection end, calculates the difference between the injection pressure and the outlet pressure, and calculates the ratio of this pressure difference to the instantaneous flow rate to obtain the circulating flow resistance value, characterizing the unobstructedness of the underground fracture network. This embodiment uses the calculated real-time thermal breakthrough rate index and circulating flow resistance value as dynamic feedback variables to provide a quantitative decision-making basis for subsequent closed-loop control.

[0081] Finally, this embodiment implements an automated closed-loop control strategy based on a PID algorithm to maintain the geothermal reservoir operating parameters within the optimal stable production range. This embodiment logically compares the real-time calculated thermal breakthrough rate index and circulating flow resistance value with a preset stable production threshold. When the monitored indicators deviate from the stable production threshold, a corresponding PID control command is automatically generated. This embodiment uses this control command to adjust the frequency converter of the injection pump unit, correcting the injection flow rate by changing the motor frequency to balance the heat exchange rate and reservoir fluid supply capacity. Simultaneously, this embodiment coordinates the adjustment of the electric actuator of the wellhead throttle valve, precisely correcting the wellhead back pressure by changing the valve opening to prevent formation fluid from flashing within the wellbore or to maintain the effective opening of fractures. Through this dual-variable coordinated adjustment mechanism, this embodiment achieves intelligent management and production capacity optimization throughout the entire lifecycle of geothermal development.

[0082] like Figure 2As shown, the injection equipment is specifically represented by the 'variable frequency injection pump set' in the figure, which provides fluid circulation power and responds to the control signal of 'flow rate regulation'. The production well and the injection well serve as a vertical channel connecting to the surface, and are connected underground through the 'fluid guiding trench' (i.e., the anti-closing channel marked in the figure) constructed in step 700. On the surface, a 'heat exchange system' (which can be used for power generation or heating) is connected in series in the pipeline to extract heat energy; the 'throttle valve' located at the outlet of the production well is the wellhead throttle valve used to perform 'back pressure regulation'. Furthermore, the edge computing unit described in the embodiment is represented in the figure as a 'PID controller / central processing unit', which is responsible for receiving real-time feedback data from the 'sensor group' (monitoring pressure, temperature, and flow rate), and coordinating the adjustment of the pump set frequency and valve opening by sending 'control signals' to achieve closed-loop control.

[0083] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0084] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A multi-level progressive dynamic-static-flexible integrated thermal storage renovation method, characterized in that, include: Obtain raw logging data for the target geothermal reservoir section; Based on the elastic wave theory formula, a rock mechanical property profile model is established according to the original well logging data, and a set of rock mechanical parameters for the target depth is obtained according to the rock mechanical property profile model. Based on the geostress calculation formula, the theoretical fracturing pressure value of conventional hydraulic fracturing is obtained according to the rock mechanics parameter set. The perforation sites are determined within the target thermal reservoir section based on the set of rock mechanics parameters, and the blasting fracturing parameters are set based on the theoretical fracturing pressure value. High-energy blasting based on the blasting fracturing parameters is performed at the perforation layer to obtain a near-wellbore low fracturing pressure pretreatment zone, wherein the near-wellbore low fracturing pressure pretreatment zone is a radially distributed well perimeter fractured area that is released from tangential stress constraint after being subjected to the blasting fracturing shock wave. Based on the guiding effect of the near-wellbore low fracturing pressure pretreatment zone, a large-volume hydraulic fracturing operation is carried out using a surface high-pressure pump set to extend and expand the near-wellbore low fracturing pressure pretreatment zone into the deep formation, thereby constructing a deep large-volume three-dimensional fracture network. The deep large-volume three-dimensional fracture network is a volumetric seepage channel that connects the natural fracture system and links the near-wellbore and the distant wellbore. A chemical stimulating medium is injected into the deep, large-volume three-dimensional fracture network, and the fracture wall of the deep, large-volume three-dimensional fracture network is non-uniformly etched according to the slow reaction characteristics of the chemical stimulating medium to obtain fluid guiding trenches. The fluid guiding trenches are uneven, anti-closing fluid flow channels formed after the removal of mineral components by chemical stimulating dissolution. The fluid diversion trench is used to construct a long-term geothermal fluid extraction circulation loop. During the operation of the long-term geothermal fluid extraction circulation loop, wellhead backflow data is collected in real time, and the injection flow rate and wellhead back pressure are dynamically adjusted based on the wellhead backflow data to achieve closed-loop optimization of the geothermal reservoir operating parameters.

2. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, The original well logging data includes: Acoustic transit time data, formation density data, and natural gamma data.

3. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, The set of rock mechanics parameters includes: Young's modulus, Poisson's ratio, and tensile strength of rock.

4. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, The rock mechanical property profile model is established based on the elastic wave theory formula and the original well logging data. Based on this model, a set of rock mechanical parameters for the target depth is obtained, including: The acoustic time difference data is converted into P-wave and S-wave velocities using the elastic wave theory formula, and the dynamic elastic modulus curve and dynamic Poisson's ratio curve are calculated based on the P-wave and S-wave velocities and the formation density data. The clay content index is calculated based on the natural gamma data, and the lithology correction coefficient is determined based on the clay content index. The dynamic elastic modulus curve and the dynamic Poisson's ratio curve are corrected by dynamic-static conversion using the lithology correction coefficient to obtain the static Young's modulus profile and the static Poisson's ratio profile. The tensile strength profile of the rock is determined based on the Griffith strength criterion and the static Young's modulus profile. The rock mechanical property profile model is constructed based on the static Young's modulus profile, the static Poisson's ratio profile, and the rock tensile strength profile. In the rock mechanical property profile model, locate the depth node corresponding to the target depth, read the feature values ​​at the depth node, and obtain the rock mechanical parameter set; The expression for the elastic wave theory formula is as follows: ； in, For the dynamic Young's modulus of rock; The dynamic Poisson's ratio of the rock; The formation density data; The longitudinal wave velocity is obtained by converting the acoustic time difference data. The transverse wave velocity is obtained by converting the acoustic time difference data. This is a unit conversion constant.

5. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, Based on the geostress calculation formula, the theoretical fracturing pressure values ​​for conventional hydraulic fracturing are obtained according to the aforementioned rock mechanics parameter set, including: The formation density data in the original well logging data is integrated at depth to obtain the vertical principal stress components at the target depth. The formation pore pressure value at the target depth is calculated based on the aforementioned acoustic transit time data; Based on the aforementioned geostress calculation formula, the vertical principal stress component, the formation pore pressure value, and the Poisson's ratio parameter are coupled and calculated to obtain the maximum horizontal principal stress value and the minimum horizontal principal stress value. Extract the tensile strength of the rock from the set of rock mechanical parameters, and construct a fracture pressure calculation model based on the maximum tensile stress criterion; The maximum horizontal principal stress value, the minimum horizontal principal stress value, the formation pore pressure value, and the rock tensile strength are substituted into the fracturing pressure calculation model to calculate the theoretical fracturing pressure value of conventional hydraulic fracturing. The expression for the geostress calculation formula is as follows: ； The calculation expression for the rupture pressure calculation model is as follows: ； in, These are the vertical principal stress components; For target depth; This is a formation density function that varies with depth; It is the acceleration due to gravity; This represents the minimum horizontal principal stress value. This represents the maximum horizontal principal stress value. The value of Poisson's ratio in the static Poisson's ratio profile; The pore pressure value of the formation; The effective stress coefficient; These are structural stress components; This refers to the theoretical fracturing pressure value of conventional hydraulic fracturing. The tensile strength of the rock is given.

6. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, The step of determining the perforation sites within the target thermal reservoir section based on the set of rock mechanics parameters, and setting the blasting fracturing parameters based on the theoretical fracturing pressure value, includes: By substituting Young's modulus and Poisson's ratio into a preset rock brittleness evaluation model, a brittleness index curve distributed along the well depth is obtained. The brittleness index curve is then coupled with the tensile strength of the rock in a weighted analysis to identify the depth range that meets the characteristics of high brittleness and low tensile strength, thereby determining the perforation layer. The overpressure coefficient is set based on the preset effective fracturing criterion, and the product of the theoretical fracturing pressure value and the overpressure coefficient is calculated to obtain the target value of the bursting peak pressure. Based on the target value of the blasting peak pressure and the wellbore geometric parameters of the perforation layer, the charge amount and combustion loading rate of the high-energy gas generator are calculated in reverse. The target value of the blasting peak pressure, the amount of explosive charge, and the combustion loading rate are encapsulated as the blasting fracturing parameters; The expression for the rock brittleness evaluation model is as follows: ； in, The brittleness index value in the brittleness index curve; The Young's modulus in the set of rock mechanical parameters; This is the normalized Young's modulus; and These represent the maximum and minimum values ​​of Young's modulus within the target well section, respectively. The normalized Poisson's ratio; and These represent the maximum and minimum Poisson's ratios within the target well section, respectively.

7. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, A high-energy blasting operation based on the aforementioned blasting fracturing parameters is performed at the perforated layer to obtain a near-wellbore low fracturing pressure pretreatment zone, including: The shaped charge fracturing device, loaded with a high-energy gas generator, is transported and positioned at the center depth of the perforation layer; The high-energy gas generator is excited by the combustion loading rate in the blasting and fracturing parameters, and releases energy instantaneously at the perforation layer to generate a transient high-pressure shock wave and high-temperature and high-pressure gas. By utilizing the dynamic impact of the transient high-pressure shock wave on the well wall rock, a fracture zone is created in the rock mass surrounding the well. Then, the gas wedge expansion effect of the high-temperature and high-pressure gas is used to drive the microcracks in the fracture zone to expand radially, forming multiple radial main cracks. Based on the opening effect of the radial main fracture, the original circumferential closed stress circle of the surrounding rock mass is destroyed to reduce the fracturing resistance of subsequent fluids entering the formation, thus obtaining the near-wellbore low fracturing pressure pretreatment zone.

8. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, The guiding effect of the flow path based on the near-wellbore low fracturing pressure pretreatment zone, and the use of surface high-pressure pump sets to carry out large-volume hydraulic fracturing operations, so as to extend and expand the near-wellbore low fracturing pressure pretreatment zone into the deep formation, constructing a deep, large-volume three-dimensional fracture network, including: Connect the ground high-pressure pump set to the wellhead, start the ground high-pressure pump set, use low-viscosity slickwater as the pre-fluid, and pump it into the wellbore with preset large-volume injection parameters. The radial main fractures in the near-wellbore low fracture initiation pressure pretreatment zone are preferentially opened using fluid pressure, and the fluid is forced to migrate along the radial main fractures toward the far end of the formation to form the main fracture channel. A proppant-carrying adhesive system is continuously pumped into the main fracture channel, and the shear slip and tensile opening of the natural fracture system on both sides of the main fracture channel are induced by the filtration effect of the high-pressure fluid, resulting in multi-level secondary fractures. The multi-level secondary fractures are controlled to interweave and connect with the main fracture channels to form a complex network structure, and the proppant is delivered into the network structure for filling and support, thereby obtaining the deep large-volume three-dimensional fracture network.

9. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, A chemically stimulating medium is injected into the deep, large-volume three-dimensional fracture network, and non-uniform etching is performed on the fracture walls of the network based on the slow-reaction characteristics of the chemically stimulating medium to obtain fluid-guiding trenches, including: The chemical stimulation medium, comprising a high-temperature slow-release acid and a viscosity control agent, is configured and injected into the deep, large-volume three-dimensional fracture network based on an injection flow rate lower than the rock fracture pressure. By utilizing the rheological properties of the viscosity control agent, a viscous fingering phenomenon is induced in the chemical stimulation medium within the crack width of the deep, large-volume three-dimensional crack network, resulting in a non-uniformly distributed dominant flow fingerprint path. Based on the dominant flow fingerprint path, the high-temperature slow acid is used to differentially dissolve the rock minerals to etch continuous grooves on the crack wall and retain the rock skeleton not covered by the dominant flow fingerprint path as a support column. The continuous groove and the support column form an uneven structure as the fluid guiding channel, and the residual acid and mineral residue after the reaction are discharged from the wellbore using the post-displacement fluid.

10. The method for comprehensive thermal storage renovation based on a multi-level progressive dynamic-static-flexible approach according to claim 1, characterized in that, The process of constructing a long-term geothermal fluid extraction circulation loop using the fluid guiding trench, acquiring wellhead flowback data in real time during the operation of the long-term geothermal fluid extraction circulation loop, and dynamically adjusting the injection flow rate and wellhead back pressure based on the wellhead flowback data to achieve closed-loop optimization of the geothermal reservoir operating parameters includes: The fluid diversion trench is connected to the ground heat exchange system, and the outlet end of the ground heat exchange system is connected back to the injection device to construct a physically closed long-term geothermal fluid extraction circulation loop. A monitoring sensor group is deployed at the fluid outlet of the long-term geothermal fluid extraction circulation loop, and the monitoring sensor group is used to collect the wellhead flowback data in real time, wherein the wellhead flowback data includes: outlet temperature, outlet pressure and instantaneous flow rate; The thermal breakthrough rate index is calculated based on the time series changes of the outlet temperature and the instantaneous flow rate, and the circulating flow resistance value is calculated based on the difference between the outlet pressure and the injection pressure. The thermal breakthrough rate index and the circulating flow resistance value are compared with the preset stable production threshold, and PID control instructions are generated based on the comparison results. The PID control command is used to adjust the frequency of the injection pump group to correct the injection flow rate, and the opening of the wellhead throttle valve is adjusted in conjunction to correct the wellhead back pressure, so as to maintain the thermal storage operating parameters within the preset stable production range.

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