A highland complex structure zone shallow drilling green exploration construction dynamic optimization system and method

Abstract

The application discloses a kind of highland complex tectonic zone shallow drill green exploration construction dynamic optimization system and method, belong to geological exploration and resource exploration engineering technical field, this system includes multi-source heterogeneous data acquisition unit, edge-cloud collaborative decision unit and closed-loop execution and verification unit, three form "real-time sensing-dynamic decision-closed loop execution-effect verification" intelligent closed loop.The method comprises: using portable drilling rig to construct pilot hole to obtain geological information;Information is input into the dynamic optimization system of built-in quantitative risk criterion for evaluation;If risk is over threshold, then execute decision instruction package to carry out equipment switching, drilling fluid performance adjustment and drilling process optimization;Synchronous implementation whole-process green control.The application reduces the construction risk and cost of drilling in highland complex tectonic zone by information-driven dynamic decision and system integration, realizes zero-pollution green exploration.

Description

Technical Field

[0001] This invention relates to the field of geological exploration and resource exploration engineering technology, and in particular to a dynamic optimization system and method for shallow drilling green exploration construction in complex plateau structural zones. Background Technology

[0002] Geological drilling in high-altitude, complex tectonic zones such as the Qiangtang Basin in the Qinghai-Tibet Plateau has long faced four major technical bottlenecks: First, the low-oxygen and low-temperature environment leads to a significant decrease in the power of conventional equipment and a reduction in the efficiency of personnel; second, permafrost and seasonally frozen soil are prone to borehole wall thawing under thermal disturbance during construction; third, the rate of stuck and buried drill bits is high when drilling in high-stress, fractured strata; and fourth, the fragile ecological environment requires near-zero pollution during construction, making it difficult for traditional methods to balance efficiency and environmental protection.

[0003] Currently, related technological improvements are mostly fragmented and lack systematic integration. Regarding equipment, while there is an invention patent, "A Transportation System and Method for Geological Drilling Equipment Applicable to Plateau Areas" (patent number: CN119370540A), which facilitates the relocation of equipment in high-altitude areas, its selection and application are static and cannot be dynamically adjusted according to actual geological conditions. In terms of processes, although there is research on specific drilling fluids for extremely cold plateau environments (such as "Low-Temperature Drilling Fluid for Drilling in Extremely Cold Plateau Environments and Its Preparation Method," patent number: CN119505841A), these are mostly isolated solutions and do not form a systematic linkage with equipment selection and environmental protection measures. Regarding environmental protection, conventional measures mostly focus on end-of-pipe treatment, lacking a comprehensive, standardized, and integrated green construction method encompassing the entire process from site planning and process control to ecological restoration.

[0004] Therefore, existing technologies lack a comprehensive solution that can dynamically optimize resource allocation based on real-time geological information and systematically integrate efficient drilling, borehole stability, and ecological protection, resulting in high costs, high risks, and significant environmental pressures in drilling operations in complex plateau geological zones. Summary of the Invention

[0005] The purpose of this invention is to overcome the technical problems existing in the prior art. Its core objective is to establish a dynamic decision-making mechanism based on pilot borehole geological information, enabling precise and economical configuration of drilling equipment and processes according to the actual geological complexity, thereby reducing construction risks and costs from the outset. It integrates specialized drilling technologies for permafrost and high-stress fractured strata (such as film-forming anti-collapse drilling fluids) with dynamic equipment allocation, forming a comprehensive technical package to overcome core geological challenges. It constructs a standardized, quantifiable, and end-to-end green exploration operation system to ensure minimal environmental impact in extremely fragile ecological areas. It also develops a dynamic optimization system integrating data acquisition, analysis, decision-making, and feedback to achieve intelligent monitoring and closed-loop optimization of the construction process, improving overall operational efficiency and safety.

[0006] To achieve the above objectives, this invention provides a comprehensive technical solution that integrates a "dynamic decision-making method", "specialized technology integration" and "intelligent optimization system".

[0007] The objective of this invention is achieved through the following technical solution: In a first aspect, the present invention provides a dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones, comprising a multi-source heterogeneous data acquisition unit interconnected via a field industrial bus or wireless network, an edge-cloud collaborative decision-making unit, and a closed-loop execution and verification unit. The multi-source heterogeneous data acquisition unit is deployed in the drilling rig body, the drill string near the drill bit area, and the drilling fluid circulation system to collect formation response parameters, equipment operating parameters, and drilling fluid performance parameters in real time. The edge-cloud collaborative decision-making unit has a built-in hierarchical hybrid risk assessment model and rule engine, which is used to dynamically identify borehole instability, equipment overload and environmental risks based on real-time data obtained by the multi-source heterogeneous data acquisition unit, and generate decision instruction packages that include equipment switching, drilling fluid performance adjustment and drilling process parameter optimization. The closed-loop execution and verification unit is used to receive and execute the decision instruction package, and after executing the decision instruction package, continuously monitor the changes of key parameters through the multi-source heterogeneous data acquisition unit. If the key parameters do not converge to the safety threshold within the set execution time window, a secondary decision or manual intervention is triggered.

[0008] In some embodiments, the multi-source heterogeneous data acquisition unit includes: The downhole measurement-while-drilling sub integrates a pressure sensor, a temperature sensor, a triaxial vibration sensor, and a torque sensor to acquire the bottom hole equivalent circulating density, annular pressure, drill string vibration characteristics, and bottom hole torque. The ground parameter acquisition terminal is connected to the drilling rig control system and the online drilling fluid monitoring instrument to collect pump pressure, pump flush, drilling speed, drilling pressure, drilling fluid density, funnel viscosity and pH value. The data transmission module uses CAN bus or RS-485 bus to collect field data and supports 4G and Beidou short message dual-link remote transmission.

[0009] In some embodiments, the hierarchical hybrid risk assessment model includes a threshold rule model, a weighted scoring model, a random forest model, and a time-series deep learning model, and different risk assessment models are adaptively selected based on the amount of local data and computing resources. The rule engine takes the risk type and probability output by the hierarchical hybrid risk assessment model as input and generates a structured decision instruction package by looking up a mapping table; the decision instruction package includes at least the instruction type, target value, execution time window and expected response parameters.

[0010] In some embodiments, the hierarchical hybrid risk assessment model includes at least one of the following quantitative risk criteria: Design hole depth increase ≥ 50%; The measured stress in the exposed strata is ≥15MPa; Pump pressure fluctuation rate ≥20% / minute and duration exceeding 2 minutes; The number of abnormal torque fluctuations exceeding the safety window is ≥3 times / hour; The mass of flaked rock fragments in the returned rock cuttings shall account for ≥ 15%; The generation of the decision instruction package includes: When any two quantitative risk criteria are triggered simultaneously, an equipment upgrade instruction is automatically generated to switch to a high-capacity drilling rig. When a single quantitative risk criterion is triggered and is related to drilling fluid performance, drilling fluid performance adjustment instructions are automatically generated, including viscosity adjustment values, filtration loss control targets, and additive dosage recommendations.

[0011] In some embodiments, the closed-loop execution and verification unit includes: The human-computer interaction terminal is set on the driller's control panel to push decision instruction packages in the form of pictures and text, and supports the driller to confirm and execute them with one click; An optional automatic execution interface is available, which connects to the automatic drilling fluid dosing device and the automatic drilling rig feed system to automatically perform drilling fluid performance adjustment and parameter optimization of drilling pressure and rotation speed under set conditions.

[0012] In some embodiments, after executing the decision instruction package, the closed-loop execution and verification unit continuously collects the same set of key parameters through the multi-source heterogeneous data acquisition unit, and performs convergence judgment within the execution time window: If the critical parameters enter the preset safety window, the system will mark it as closed-loop convergence and continue regular monitoring; If the key parameters fail to converge or worsen further, the system will automatically trigger a secondary decision and mark the data for that period as a high-risk event, uploading it to the cloud for model iteration.

[0013] In some embodiments, the safety window for convergence determination includes: Pump pressure fluctuation rate ≤10% / minute; Torque fluctuation ≤15%; Viscosity fluctuation in the drilling fluid funnel ≤ ±3s; The mass of the broken rock fragments returned should be ≤8%.

[0014] In some embodiments, the system is also integrated with a green construction standardized operation system to achieve at least the following functions: Site seepage prevention monitoring: Monitoring the integrity and coverage of high-strength seepage-proof fabric through image recognition or sensors; Waste closed-loop management monitoring: Real-time monitoring of the reuse rate of the drilling fluid closed-loop circulation system, the processing capacity of the mobile synchronous solidification device, and the moisture content of the solidified cake. Ecological restoration verification: After the hole is closed, record the amount of sealing material used, the list of recyclable materials on site, and the area of ​​vegetation restoration, and generate a green construction closed-loop report.

[0015] In some embodiments, the system automatically generates an environmental warning instruction when any of the following indicators exceed a threshold: Drilling fluid reuse rate < 85%; The solidified cake has a moisture content > 35% after curing; The damaged area of ​​the impermeable fabric is greater than 1 m².

[0016] A second aspect of the present invention provides a dynamic optimization method for shallow drilling green exploration construction in complex plateau structural zones, employing the system described in the first aspect, and comprising the following steps: S1: In the pilot exploration stage, a pilot hole is constructed using a first lightweight drilling rig to obtain geological and engineering information, including the depth of frozen soil, the characteristics of fracture zone development, and rock drillability data. S2: In the dynamic evaluation phase, the geological and engineering information obtained from the pilot hole is input into the edge-cloud collaborative decision-making unit, and a risk assessment is conducted based on the quantitative risk criteria. S3: During the construction optimization phase, if the risk assessment exceeds the threshold, the decision instruction package generated by the closed-loop execution and verification unit is executed to perform equipment switching, drilling fluid performance adjustment and drilling process optimization. S4: Green management throughout the entire process, simultaneously implementing site seepage prevention, closed-loop circulation of drilling fluid, simultaneous solidification of waste and ecological restoration at the end of the borehole.

[0017] It should be further noted that the technical features corresponding to the above-mentioned options and embodiments can be combined or substituted with each other to form new technical solutions without conflict.

[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. Significantly Reduced Construction Risks: This invention accurately acquires geological information through pilot holes and combines it with quantitative risk criteria in a dynamic optimization system (including design hole depth increase ≥50%, measured stress ≥15MPa, pump pressure fluctuation rate ≥20% / minute, etc.) for precise risk assessment. When the risk exceeds the threshold, it executes instructions for equipment switching, drilling fluid performance adjustment, and process optimization. This flexible workflow of "pilot exploration → quantitative assessment → dynamic decision-making" avoids major in-hole accidents such as stuck drill bits and buried drill bits caused by insufficient equipment capacity or process mismatch. Example data shows that the accident rate can be reduced to below 3% after adopting this invention, far lower than the average level of over 15% in similar projects.

[0019] 2. Effective Control of Construction Costs: Although this invention adds a pilot hole construction step, a quantitative judgment triggering mechanism ensures that equipment upgrades are initiated only when necessary (e.g., switching from a first lightweight drilling rig to a second high-capacity drilling rig), avoiding the enormous costs of blindly using large drilling rigs for full-well construction. Simultaneously, the closed-loop execution and verification unit performs convergence judgment within the execution time window (e.g., 30 minutes after the execution command). If convergence fails, a secondary decision is triggered, avoiding the high handling costs resulting from escalating accidents. Example data shows that the overall cost is reduced by approximately 20% compared to traditional solutions.

[0020] 3. Significantly Improved Environmental Protection: This invention simultaneously implements green management throughout the entire process and integrates with a standardized green construction operation system. Specifically, it achieves "workbench deployment" through site seepage monitoring, achieves closed-loop management and monitoring of waste to ensure closed-loop circulation of drilling fluid (drilling fluid reuse rate >90%) and simultaneous on-site solidification of rock cuttings and waste slurry (moisture content <30% after solidification), and ensures 100% controlled disposal of waste. Ecological restoration verification demonstrates the use of environmentally friendly materials for sealing boreholes and restoring vegetation after drilling completion. Example data shows that after ecological restoration, the vegetation coverage rate reaches 99%, with no significant difference from the surrounding natural meadows.

[0021] 4. Achieving Intelligent Closed-Loop Optimization: The core of this invention lies in the three-unit architecture that forms a dynamic optimization closed loop for the construction process, encompassing "real-time perception - dynamic decision-making - closed-loop execution - effect verification." Specifically, the multi-source heterogeneous data acquisition unit provides high-density real-time data at a frequency of no less than once every 30 seconds; the edge-cloud collaborative decision-making unit incorporates a hierarchical hybrid model (threshold rule model, weighted scoring model, random forest model, and optional temporal deep learning model), adaptively selecting the model level based on the data volume, and generating structured decision instruction packages through a rule engine (risk-action mapping table); after execution, effect verification is performed through convergence judgment. This achieves closed-loop control throughout the entire process from data acquisition and risk assessment to instruction execution and effect verification. In particular, through the synergy of the hierarchical hybrid model and the rule engine, a balance is achieved between "high-sensitivity early warning (false alarm rate <10%)" and "low false alarm rate (<15%)" in the extreme plateau environment, significantly outperforming conventional threshold methods. Attached Figure Description

[0022] Figure 1 This is a flowchart illustrating a dynamic optimization method for shallow drilling green exploration in complex plateau structural zones, as shown in an embodiment of the present invention. Figure 2 This is a schematic diagram of the hierarchical hybrid risk assessment model structure shown in an embodiment of the present invention; Figure 3 This is a flowchart illustrating the generation process of the decision instruction package of the rule engine in an embodiment of the present invention. Figure 4This is a diagram illustrating the dynamic device optimization and decision-making logic based on pilot hole information, as shown in an embodiment of the present invention. Figure 5 This is a top view of a standardized well site layout on a plateau, as shown in an embodiment of the present invention. Detailed Implementation

[0023] The technical solution 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, not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. 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.

[0024] It should be noted that the defects in the solutions in the prior art are all the results of the inventors' practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed by the embodiments of this application in the following text should be the inventors' contributions to this application in the process of invention and creation, and should not be understood as technical content known to those skilled in the art.

[0025] In view of the technical problems pointed out in the background art, the present invention provides the following embodiments: In an exemplary embodiment, a dynamic optimization system for shallow drilling green exploration construction in complex plateau structural zones is provided, including a multi-source heterogeneous data acquisition unit, an edge-cloud collaborative decision-making unit, and a closed-loop execution and verification unit interconnected via a field industrial bus or wireless network, forming a dynamic optimization closed loop for the construction process of "real-time perception - dynamic decision-making - closed-loop execution - effect verification". The multi-source heterogeneous data acquisition unit is deployed in the drilling rig body, the drill string near the drill bit area and the drilling fluid circulation system to collect formation response parameters, equipment operating parameters and drilling fluid performance parameters in real time, and transmit them to the edge-cloud collaborative decision-making unit at a frequency of no less than once every 30 seconds. The edge-cloud collaborative decision-making unit has a built-in hierarchical hybrid risk assessment model and rule engine, which is used to dynamically identify borehole instability, equipment overload and environmental risks based on real-time data obtained by the multi-source heterogeneous data acquisition unit, and generate decision instruction packages that include equipment switching, drilling fluid performance adjustment and drilling process parameter optimization. The closed-loop execution and verification unit, together with the multi-source heterogeneous data acquisition unit and the edge-cloud collaborative decision-making unit, forms a data closed loop. It is used to receive and execute the decision instruction package, and after executing the decision instruction package, it continuously monitors the changes of key parameters through the multi-source heterogeneous data acquisition unit. If the key parameters do not converge to the safety threshold within the set execution time window, it triggers secondary decision-making or manual intervention.

[0026] Furthermore, the multi-source heterogeneous data acquisition unit includes: The downhole measurement-while-drilling sub integrates a pressure sensor, a temperature sensor, a triaxial vibration sensor, and a torque sensor. It is located 5 to 15 meters behind the drill bit and is used to obtain the equivalent circulating density at the bottom of the hole, annular pressure, drill string vibration characteristics, and bottom hole torque. The ground parameter acquisition terminal is connected to the drilling rig control system and the online drilling fluid monitoring instrument to collect pump pressure, pump flush, drilling speed, drilling pressure, drilling fluid density, funnel viscosity and pH value. The data transmission module uses CAN bus or RS-485 bus to collect field data and supports 4G and Beidou short message dual-link remote transmission.

[0027] The data acquisition frequency of the downhole measurement while drilling sub is no less than once every 30 seconds, and the data acquisition frequency of the ground parameter acquisition terminal is no less than once every 10 seconds.

[0028] Furthermore, the hierarchical hybrid risk assessment model described in this invention is not a single fixed model, such as... Figure 2 As shown, this includes threshold rule models, weighted scoring models, random forest models, and time-series deep learning models. Different risk assessment models are adaptively selected based on the amount of local data and computing resources. For example: L1 Threshold Rule Model (Baseline): Applicable when there is no historical data and only the pilot hole stage is completed, directly compares the measured value with the criterion threshold to output the risk level (low / medium / high). L2 weighted scoring model (lightweight): suitable for those with a small amount of local data (<50 groups), outputting risk probabilities based on feature weighted summation; L3 Random Forest Model (Recommended): Suitable for those with sufficient local data (≥50 sets). Input 12-dimensional features (frozen soil thickness, fracture zone depth, rock drillability, in-situ stress, drill pressure, rotation speed, pump pressure, torque, mechanical drilling speed, annular return speed, funnel viscosity, API filtration loss), output risk type and probability; L4 Temporal Deep Learning Model (Optional): Suitable for continuous operation of multiple wells with sufficient data, it provides early warning 15-30 minutes in advance based on 30-minute sliding window data.

[0029] The input features of the stratified hybrid risk assessment model include 12 parameters: permafrost thickness, fracture zone depth, rock drillability, in-situ stress, drill pressure, rotational speed, pump pressure, torque, mechanical drilling speed, annular return velocity, funnel viscosity, and API filtration loss. Feature importance is determined based on mutual information and Shapley values. The model is updated in the field through incremental learning and transfer learning. For example, the initial weights of feature importance are determined based on mutual information of historical data from multiple wells (no less than 10) in the Qiangtang Basin. After completing 5 wells or accumulating 100 sets of high-risk samples in the field, the Shapley value is recalculated through incremental learning. The model update adopts a combination of transfer learning (fine-tuning with pilot hole data) and incremental training (triggered every 30 sets of new data) to ensure that the model always adapts to the current formation characteristics.

[0030] like Figure 3 As shown, the rule engine takes the risk type and probability output by the hierarchical hybrid risk assessment model as input, and generates a structured decision instruction package by looking up a mapping table (risk-action mapping table); the rule base of the rule engine consists of the following three parts: (1) Domain knowledge rules: Based on the experience of experts in the field of plateau drilling, the empirical knowledge such as "when the pump pressure increases suddenly and the torque fluctuates, the viscosity of the drilling fluid should be increased" is formalized into executable "condition-action" rules.

[0031] (2) Accident inversion rules: Analyze the pre-accident data of historical accident wells and invert rules such as "when the measured stress is ≥15MPa and the mechanical drilling speed decreases by ≥30%, the probability of stuck drill increases significantly". After expert review, the rules are entered into the database.

[0032] (3) Data mining rules (optional): Strongly correlated feature combinations discovered during model training are periodically added to the rule base after being confirmed by experts.

[0033] The decision instruction package includes at least the instruction type, target value, execution time window, and expected response parameters. Instruction types include equipment switching, drilling fluid adjustment, and process parameter adjustment. Target values ​​include, for example, increasing funnel viscosity to 25–30 s and reducing drilling pressure to 15 kN. Table 1 shows some core decision rules and examples of decision instructions.

[0034] Table 1. Examples of Core Decision-Making Rules and Decision-Making Instructions Furthermore, the hierarchical hybrid risk assessment model includes at least one of the following quantitative risk criteria: Design hole depth increase ≥ 50%; The measured stress in the exposed strata is ≥15MPa; Pump pressure fluctuation rate ≥20% / minute and duration exceeding 2 minutes; The number of abnormal torque fluctuations exceeding the safety window is ≥3 times / hour; The mass of flaked rock fragments in the returned rock cuttings shall account for ≥ 15%; The generation of the decision instruction package includes: When any two quantitative risk criteria are triggered simultaneously, an equipment upgrade instruction is automatically generated to switch to a high-capacity drilling rig. When a single quantitative risk criterion is triggered and is related to drilling fluid performance, drilling fluid performance adjustment instructions are automatically generated, including viscosity adjustment values, fluid loss control targets, and additive dosage recommendations. Specifically, based on the above quantitative risk criteria, the mapping table includes at least the following decision rules: ① When the pump pressure fluctuation rate is ≥20% / min and the torque fluctuation amplitude is ≥15%, an instruction is generated to immediately increase the drilling fluid viscosity to 28~32s and reduce the drilling pressure by 20%; ② When the proportion of broken pieces in the returned rock cuttings is ≥15% and the pump pressure is stable, an instruction is generated to increase the amount of film-forming agent by 0.2%~0.3% and reduce the discharge volume by 10%; ③ When the measured stress is ≥15MPa and the mechanical drilling speed decreases by ≥30%, an instruction is generated to switch to screw motor + wireline coring composite drilling and reduce the drilling pressure to 12~15kN; ④ When the API filtration loss of drilling fluid is >15mL / 30min and the sharpness of the returned cuttings increases, an instruction is generated to supplement 1%~1.5% composite film-forming agent and increase the pH to 12~13; ⑤ When the hole depth increases by ≥50% and the stress in the fracture zone exposed by the pilot hole is ≥18MPa, an equipment upgrade instruction is generated.

[0035] The values ​​of the quantitative risk criteria, such as the pump pressure fluctuation threshold of 20% / min, the stress threshold of 15MPa, the blockage ratio threshold of 15%, and the upper limit of API filtration loss of 15mL, are based on ROC curve analysis of multiple historical drilling data (no less than 10 wells) in the Qiangtang Basin of the Qinghai-Tibet Plateau, and are obtained by introducing correction coefficients for altitude, temperature, and oxygen content. The false alarm rate is less than 15% and the false alarm rate is less than 10%. For example, historical data collection included complete drilling time data from multiple (more than 10) geological drilling wells completed in the Qiangtang Basin (average altitude 4800-5200 meters) between 2012 and 2024. This included multiple sets of valid samples of marked in-hole accident records (6 stuck drill incidents, 2 burial drill incidents, and 5 severe wellbore collapses) and records of normal drilling sections. During data analysis, a sliding window statistical analysis was performed on key parameters within 30 minutes before each well accident. The pre-accident characteristic value was used as a positive sample, and the normal drilling section as a negative sample. ROC curves for each parameter were plotted, and the optimal cutoff value was determined by maximizing the Youden index. Then, based on the optimal cutoff value, a plateau correction factor was introduced—for every 1000-meter increase in altitude, the pump pressure fluctuation threshold decreased by 3%; for every 10°C decrease in temperature, the stress threshold decreased by 5%. Finally, prospective validation was conducted in subsequent validation wells, and the final criterion set had a false alarm rate of <15% and a false negative rate of <10%.

[0036] Furthermore, the closed-loop execution and verification unit includes: The human-computer interaction terminal is set on the driller's control panel to push decision instruction packages in the form of pictures and text, and supports the driller to confirm and execute them with one click; An optional automatic execution interface is available, which connects to the automatic drilling fluid dosing device and the automatic drilling rig feed system to automatically perform drilling fluid performance adjustment and parameter optimization of drilling pressure and rotation speed under set conditions.

[0037] Furthermore, after executing the decision instruction package, the closed-loop execution and verification unit continuously collects the same set of key parameters through the multi-source heterogeneous data acquisition unit, and performs convergence judgment within the execution time window (e.g., 30 minutes). If the critical parameters enter the preset safety window, the system will mark it as closed-loop convergence and continue regular monitoring; If key parameters fail to converge or worsen further, the system automatically triggers a secondary decision and marks the data for that period as a high-risk event, uploading it to the cloud for model iteration. For example... Figure 4 As shown, a dynamic equipment optimization and decision-making logic diagram based on pilot hole information is presented.

[0038] Furthermore, the safety window for the convergence determination includes: Pump pressure fluctuation rate ≤10% / minute; Torque fluctuation ≤15%; Viscosity fluctuation in the drilling fluid funnel ≤ ±3s; The mass of the broken rock fragments returned should be ≤8%.

[0039] Based on the aforementioned optimized system, this invention integrates a high-efficiency film-forming and anti-collapse drilling fluid system with a compatible composite drilling process. The high-efficiency film-forming and anti-collapse drilling fluid system targets permafrost thawing and fracture zone instability, utilizing a specialized drilling fluid capable of forming a dense isolation film on the borehole wall. This system uses a composite polymer film-forming agent as its core, supplemented with a low-temperature stabilizer, ensuring effective sealing of fractures at low temperatures. Key performance indicators include: funnel viscosity 20–30 s, density 1.05–1.10 g / cm³, API filtration loss ≤15 mL, mud cake thickness ≤1 mm, and pH value 12–14.

[0040] The adaptable composite drilling technology uses casing drilling for rapid isolation in shallow frozen soil layers; and adopts a "screw motor + wireline coring" composite drilling in deep fractured zones, which improves coring rate and efficiency while controlling hole inclination.

[0041] Furthermore, such as Figure 5 As shown, a top view of a standardized well site layout in a plateau region is presented. It can be seen that this system is integrated with the green construction standardized operation system and achieves at least the following functions: Site seepage prevention monitoring: Monitoring the integrity and coverage of high-strength seepage-proof fabric through image recognition or sensors; Waste closed-loop management monitoring: Real-time monitoring of the reuse rate of the drilling fluid closed-loop circulation system, the processing capacity of the mobile synchronous solidification device, and the moisture content of the solidified cake. Ecological restoration verification: After the hole is closed, record the amount of sealing material used, the list of recyclable materials on site, and the area of ​​vegetation restoration, and generate a green construction closed-loop report.

[0042] Based on this, the present invention transforms environmental protection requirements into standardized operations that can be performed on-site: The entire work area is protected against seepage: all equipment and activities are carried out on the laid high-strength impermeable fabric, realizing "workbench fabricization"; "No-landing" closed-loop management of waste: Drilling fluid is purified by a closed-loop system consisting of "vibrating screen - mud cleaner - circulation tank" with a reuse rate of >90%; rock cuttings and waste slurry are processed on-site into solid cakes by a mobile synchronous solidification device before being transported off-site. Ecological in-situ restoration: After the borehole is closed, environmentally friendly materials are used to seal the borehole, all man-made objects are recycled, and soil is backfilled and vegetation is restored according to the original appearance.

[0043] Furthermore, the system automatically generates an environmental protection early warning instruction when any of the following indicators exceed a threshold: Drilling fluid reuse rate < 85%; The solidified cake has a moisture content > 35% after curing; The damaged area of ​​the impermeable fabric is greater than 1 m².

[0044] In another exemplary embodiment, a dynamic optimization method for shallow drilling green exploration construction in complex plateau structural zones is provided based on the above system. This method abandons the static, one-time equipment selection model and establishes a flexible workflow of "pilot exploration → quantitative assessment → dynamic decision-making," such as... Figure 1 As shown, it includes the following steps: S1: In the pilot exploration stage, a pilot hole is constructed using a lightweight drilling rig (such as the XY-44A type) to quickly obtain geological and engineering information at the lowest cost. The geological and engineering information includes first-hand geological and engineering data such as the depth of permafrost, the development characteristics of fracture zones, and the drillability of rocks. S2: In the dynamic evaluation phase, the geological and engineering information obtained from the pilot borehole is input into the edge-cloud collaborative decision-making unit, and a risk assessment is conducted based on the quantitative risk criteria. This step establishes clear quantitative risk assessment criteria, including: whether the design borehole depth increase is ≥50%, whether there is a high-stress fracture zone with stress ≥15MPa, whether the frequency of complex conditions inside the borehole exceeds the limit, etc., and the pilot borehole data is used for evaluation.

[0045] S3: During the construction optimization phase, if the risk assessment exceeds the threshold, the decision instruction package generated by the closed-loop execution and verification unit is executed to perform equipment switching, drilling fluid performance adjustment and drilling process optimization. S4: Green management throughout the entire process, simultaneously implementing site seepage prevention, closed-loop circulation of drilling fluid, simultaneous solidification of waste and ecological restoration at the end of the borehole.

[0046] Furthermore, in step S3, if the assessed risk exceeds the threshold, an optimization procedure is immediately initiated. This includes, for example, equipment switching, where the drilling rig is upgraded to a more capable device (such as the HXY-6B model) at the construction site, and hole relocation or continuous drilling is performed, achieving an economical and rapid transition from "reconnaissance" to "intensive drilling." Specifically, equipment switching includes: relocating the hole 5-15 meters beside the pilot hole, upgrading the first lightweight drilling rig to a second drilling rig with a rated drilling depth capacity of not less than 1500 meters, and lowering technical casing to seal the frozen soil layer and fractured zone.

[0047] Based on the above system and method, this invention is illustrated by taking the "Tuodi 1 Well" drilling project in the Qiangtang Basin of the Qinghai-Tibet Plateau as an example, specifically including: 1. Project Overview and Initial Challenges The "Tuodi-1 Well" is located in the Tuonamu area of ​​the Qiangtang Basin, at an average altitude of 5,000 meters, within a typical high-altitude complex tectonic zone. The initial design was a 300-meter shallow borehole for geological surveying. The site faces four core challenges: (1) Low oxygen and low temperature - oxygen content 13.5%, lowest temperature -38℃ - leading to a decrease in equipment efficiency; (2) There is a permafrost layer with a thickness of 80 to 120 meters, and the borehole wall has poor thermal stability; (3) Geological data predicts that there may be a high-stress fracture zone at depth, which poses a high risk of stuck drill bit; (4) The site is a native meadow with a fragile ecosystem and extremely high environmental protection requirements.

[0048] 2. Implementation Process The implementation of the method and system described in this invention in this project strictly follows the process of "pilot exploration, dynamic decision-making, optimized construction, and green closed loop".

[0049] (1) Pilot hole construction and precise information acquisition Abandoning the traditional practice of directly using large drilling rigs, the modular and lightweight XY-44A vertical shaft drilling rig was first selected to construct the pilot hole. The borehole diameter was Φ98mm, and wireline coring was used to drill to a final depth of 300 meters. The entire construction process was guided by UAV aerial surveying, strictly limiting the working area to 4.5 meters wide, and high-strength impermeable fabric was laid throughout.

[0050] The core achievement of this phase was obtaining accurate "geological-engineering" diagnostic data: The burial depths of the top and bottom slabs of the frozen soil layer are clearly defined as 12 meters and 108 meters, respectively. For the first time, a thick, high-stress fracture zone that was not fully shown in previous data was revealed in the 250-300 meter borehole section, and the core was extremely fractured; The records show that the pump pressure fluctuated significantly during drilling in this section, and there were frequent rockfalls. The initial assessment is that the in-situ stress value is in the range of 18 to 22 MPa.

[0051] The heart rate reached 92% at this stage, providing a high-quality information basis for decision-making.

[0052] (2) Dynamic risk assessment and optimization decision-making The information obtained from the pilot hole is input into the dynamic optimization system of this invention for analysis. The system performs an evaluation based on a preset risk quantification model: Criterion 1: The target layer was adjusted, and the designed hole depth was increased from 300 meters to 800 meters, an increase of 167% (>50% threshold). Criterion 2: A high-stress fracture zone has been exposed, and the measured stress estimate exceeds 18 MPa (>15 MPa threshold). Criterion 3: When the pilot hole is being constructed in a fractured zone, the frequency of complex situations inside the hole far exceeds the safety threshold.

[0053] The system determined that the torque, lifting force, and accident handling capabilities of the original XY-44A drilling rig were insufficient to meet the requirements for safely traversing a fractured zone at a depth of 800 meters, classifying the risk level as "high." Based on this, a dynamic optimization decision was initiated: the pilot hole was retained as a data access hole, a new location was selected 8 meters to its side, and the HXY-6B core drilling rig was used for the relocation drilling.

[0054] (3) Optimize resource allocation and integrated construction The HXY-6B drilling rig (rated drilling depth ≥1500 meters) was in place. Based on the geological information revealed by the pilot borehole, the borehole structure was optimized: after opening the Φ95mm hole, a Φ122mm technical casing was promptly installed to precisely seal the 12-108m frozen soil layer and the 250-300m severely fractured zone, thus creating a stable window for deep drilling.

[0055] Regarding the drilling fluid system, the film-forming and anti-collapse drilling fluid system described in this invention was fully applied. A drilling fluid was prepared on-site, with a composite polymer film-forming agent (0.8%) and a low-temperature stabilizer (0.4%) as its core components, achieving stable performance at: viscosity 22s, density 1.07 g / cm³, API filtration loss 12 mL / 30min, and mud cake thickness 0.8 mm. This system formed an effective isolation film on the fractured wellbore, and observations showed that the phenomenon of cuttings falling during return was reduced by more than 70% compared to the pilot hole section during the same period.

[0056] In terms of drilling technology, the "screw motor + wireline coring" composite drilling technology is adopted in the 300-800 meter deep high-stress fracture zone. Combined with high-strength diamond drill bits, the average mechanical drilling speed reaches 1.5 m / h, the hole inclination accuracy is controlled within 0.4° / 100m, and the coring rate is increased to 96%.

[0057] Regarding green construction throughout the entire process, the green standards described in this invention are strictly implemented. The drilling fluid closed-loop circulation system operates continuously, and the drilling fluid reuse rate reaches 93%. All rock cuttings and waste slurry are treated on-site by adding 6% solidifying agent to a mobile synchronous solidification device (processing capacity 6m³ / h) to form solid cakes with a moisture content of <30%, which are then sealed and transported away.

[0058] In terms of intelligent system monitoring, the supporting dynamic optimization system operates in real time. The data acquisition unit collects parameters such as borehole pressure, torque, and sand return status every 10 minutes. When drilling reached 520 meters and 650 meters, the system data analysis unit twice issued early warnings of potential borehole instability risks based on sudden increases in pump pressure and abnormal fluctuations in torque, 10-15 minutes in advance. The execution unit immediately prompted the driller to adjust the drilling fluid properties (slightly increasing the viscosity-shear force), successfully avoiding a stuck pipe accident.

[0059] (4) On-site verification and special effects of risk criterion threshold In this embodiment, the pump pressure fluctuation rate threshold is set to 20% / min. When drilling reaches 520 meters, the pump pressure fluctuation rate rises from 15% to 21%, and the system immediately triggers the R01 rule, generating instructions to increase the drilling fluid viscosity to 28-32s and reduce the drilling pressure by 20%. The driller completes the adjustment within 15 minutes, and the borehole instability is controlled. If the conventional plain value of 30% / min is used, this fluctuation will not trigger an early warning, and the processing window will be missed. In fact, in the same area, several other control wells that did not use this invention (such as Qiangzi 1 and Qiangzi 2 wells) experienced stuck drill accidents due to excessively high pump pressure fluctuation threshold settings and failure to provide timely warnings, with an average processing time of over 72 hours. This indicates that the criterion values ​​used in this invention are specifically obtained through statistical analysis and field verification for extreme plateau environments, possessing unique technical effects that cannot be obtained through a limited number of tests.

[0060] (5) Completion and Ecological Restoration After drilling, M12 grade environmentally friendly cement slurry was used for sealing the entire well section. Acoustic amplitude testing showed a 100% pass rate for the sealing quality. After construction, all equipment and materials (including the impermeable fabric) were recycled. After site leveling, ecological restoration was carried out using a combination of transplanting native turf and reseeding with local grass species. Monitoring the following year showed that the vegetation coverage in the construction area reached 99%, with no significant difference from the surrounding natural meadows.

[0061] 3. Implementation Results By fully applying this invention in this project, quantifiable and verifiable technical and economic benefits have been achieved: Construction safety and efficiency: 800 meters of drilling was successfully completed without any major in-hole accidents, with an accident rate of approximately 3%, significantly lower than the average level of over 15% for similar projects in the region; the total construction period was shortened by approximately 12% compared to the original estimated period for direct construction using a medium-sized drilling rig.

[0062] Cost control: The total cost is about 20% lower than the conventional "directly select large drilling rigs to ensure safety" approach.

[0063] Environmental benefits: Drilling fluid material consumption is reduced by more than 30%, waste is 100% controlled and zero-pollution, and ecological restoration meets and exceeds design standards.

[0064] Technical verification: The effectiveness of the "dynamic decision-making based on pilot hole information" logic was successfully verified, as well as the advanced nature of the integration of "film-forming drilling fluid system", "modular green process" and "intelligent optimization system".

[0065] The above detailed embodiments are a description of the present invention. It should not be considered that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, several simple deductions and substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the protection scope of the present invention.

Claims

1. A dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones, characterized in that, This includes a multi-source heterogeneous data acquisition unit interconnected via field industrial bus or wireless network, an edge-cloud collaborative decision-making unit, and a closed-loop execution and verification unit; The multi-source heterogeneous data acquisition unit is deployed in the drilling rig body, the drill string near the drill bit area, and the drilling fluid circulation system to collect formation response parameters, equipment operating parameters, and drilling fluid performance parameters in real time. The edge-cloud collaborative decision-making unit has a built-in hierarchical hybrid risk assessment model and rule engine, which is used to dynamically identify borehole instability, equipment overload and environmental risks based on real-time data obtained by the multi-source heterogeneous data acquisition unit, and generate decision instruction packages that include equipment switching, drilling fluid performance adjustment and drilling process parameter optimization. The closed-loop execution and verification unit is used to receive and execute the decision instruction package, and after executing the decision instruction package, continuously monitor the changes of key parameters through the multi-source heterogeneous data acquisition unit. If the key parameters do not converge to the safety threshold within the set execution time window, a secondary decision or manual intervention is triggered.

2. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 1, characterized in that, The multi-source heterogeneous data acquisition unit includes: The downhole measurement-while-drilling sub integrates a pressure sensor, a temperature sensor, a triaxial vibration sensor, and a torque sensor to acquire the bottom hole equivalent circulating density, annular pressure, drill string vibration characteristics, and bottom hole torque. The ground parameter acquisition terminal is connected to the drilling rig control system and the online drilling fluid monitoring instrument to collect pump pressure, pump flush, drilling speed, drilling pressure, drilling fluid density, funnel viscosity and pH value. The data transmission module uses CAN bus or RS-485 bus to collect field data and supports 4G and Beidou short message dual-link remote transmission.

3. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 1, characterized in that, The hierarchical hybrid risk assessment model includes threshold rule model, weighted scoring model, random forest model and time series deep learning model, and different risk assessment models are adaptively selected according to the amount of local data and computing resources; The rule engine takes the risk type and probability output by the hierarchical hybrid risk assessment model as input and generates a structured decision instruction package by looking up a mapping table; the decision instruction package includes at least the instruction type, target value, execution time window and expected response parameters.

4. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 3, characterized in that, The hierarchical hybrid risk assessment model includes at least one of the following quantitative risk criteria: Design hole depth increase ≥ 50%; The measured stress in the exposed strata is ≥15MPa; Pump pressure fluctuation rate ≥20% / minute and duration exceeding 2 minutes; The number of abnormal torque fluctuations exceeding the safety window is ≥3 times / hour; The mass of flaked rock fragments in the returned rock cuttings shall account for ≥ 15%; The generation of the decision instruction package includes: When any two quantitative risk criteria are triggered simultaneously, an equipment upgrade instruction is automatically generated to switch to a high-capacity drilling rig. When a single quantitative risk criterion is triggered and is related to drilling fluid performance, drilling fluid performance adjustment instructions are automatically generated, including viscosity adjustment values, filtration loss control targets, and additive dosage recommendations.

5. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 1, characterized in that, The closed-loop execution and verification unit includes: The human-computer interaction terminal is set on the driller's control panel to push decision instruction packages in the form of pictures and text, and supports the driller to confirm and execute them with one click; An optional automatic execution interface is available, which connects to the automatic drilling fluid dosing device and the automatic drilling rig feed system to automatically perform drilling fluid performance adjustment and parameter optimization of drilling pressure and rotation speed under set conditions.

6. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 1, characterized in that, After executing the decision instruction package, the closed-loop execution and verification unit continuously collects the same set of key parameters through the multi-source heterogeneous data acquisition unit, and performs convergence judgment within the execution time window. If the critical parameters enter the preset safety window, the system will mark it as closed-loop convergence and continue regular monitoring; If the key parameters fail to converge or worsen further, the system will automatically trigger a secondary decision and mark the data for that period as a high-risk event, uploading it to the cloud for model iteration.

7. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 6, characterized in that, The safety window for convergence determination includes: Pump pressure fluctuation rate ≤10% / minute; Torque fluctuation ≤15%; Viscosity fluctuation in the drilling fluid funnel ≤ ±3s; The mass of the broken rock fragments returned should be ≤8%.

8. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 1, characterized in that, The system is also integrated with the green construction standardized operation system, and at least achieves the following functions: Site seepage prevention monitoring: Monitoring the integrity and coverage of high-strength seepage-proof fabric through image recognition or sensors; Waste closed-loop management monitoring: Real-time monitoring of the reuse rate of the drilling fluid closed-loop circulation system, the processing capacity of the mobile synchronous solidification device, and the moisture content of the solidified cake. Ecological restoration verification: After the hole is closed, record the amount of sealing material used, the list of recyclable materials on site, and the area of ​​vegetation restoration, and generate a green construction closed-loop report.

9. The dynamic optimization system for shallow drilling green exploration and construction in complex plateau structural zones according to claim 8, characterized in that, The system automatically generates an environmental protection early warning command when any of the following indicators exceed the threshold: Drilling fluid reuse rate < 85%; The solidified cake has a moisture content > 35% after curing; The damaged area of ​​the impermeable fabric is greater than 1 m².

10. A dynamic optimization method for shallow drilling green exploration construction in complex plateau structural zones, employing the system described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1: In the pilot exploration stage, a pilot hole is constructed using a first lightweight drilling rig to obtain geological and engineering information, including the depth of frozen soil, the characteristics of fracture zone development, and rock drillability data. S2: In the dynamic evaluation phase, the geological and engineering information obtained from the pilot hole is input into the edge-cloud collaborative decision-making unit, and a risk assessment is conducted based on the quantitative risk criteria. S3: During the construction optimization phase, if the risk assessment exceeds the threshold, the decision instruction package generated by the closed-loop execution and verification unit is executed to perform equipment switching, drilling fluid performance adjustment and drilling process optimization. S4: Green management throughout the entire process, simultaneously implementing site seepage prevention, closed-loop circulation of drilling fluid, simultaneous solidification of waste and ecological restoration at the end of the borehole.

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