Submarine heavy placer rapid detection method based on shipborne pull-type combined measurement

Abstract

The invention relates to the technical field of marine geological resource exploration, in particular to a rapid seabed heavy placer detection method based on shipborne pull-type combined measurement, which comprises the following steps: S1, connecting a pull body integrating a gamma-ray spectrum detection assembly, a magnetic susceptibility detection assembly and a pressure-bearing sealing structure with a shipborne integrated control host through a cable; s2, acquiring gamma-ray spectrum data and sediment magnetic susceptibility; s3, performing water depth pressure compensation correction on the gamma-ray spectrum data, and performing inclination angle correction on the magnetic susceptibility data; s4, converting the corrected gamma-ray spectrum data into a radioactivity abnormal intensity graph, and converting the corrected magnetic susceptibility data into a magnetic susceptibility abnormal intensity graph; and S5, spatial superposition is carried out, and a heavy placer target area is screened out. According to the method, through integration of a multi-parameter detection and correction mechanism, accurate identification and standardized output of the seabed heavy placer abnormal region are realized, and the reliability and the judgment efficiency of near-bottom layer resource detection are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of marine geological resource exploration, and particularly to a rapid detection method for submarine placer deposits based on shipborne towed joint measurement. Background Art

[0002] In the process of submarine mineral resource exploration, placer deposits (including gold, iron, rare earth, etc.) have become important exploration targets for shallow subsurface target resources due to their high economic value and clear occurrence characteristics; currently, using a shipborne measurement platform combined with underwater towed equipment to conduct near-bottom detection has become the mainstream technical route, and the detection parameters mainly include physical field data such as radioactive gamma energy spectrum, magnetic susceptibility response, and conductivity; among them, internationally, gamma energy spectrum is widely used to reflect the enrichment characteristics of radioactive elements in heavy minerals, and magnetic susceptibility is used to reflect the occurrence degree of magnetic minerals, and the two are highly complementary in expressing the distribution characteristics of placer deposits; however, traditional exploration methods mainly focus on single-parameter analysis, ignoring the quantitative identification of the spatial coincidence characteristics of multi-parameters, resulting in large errors in target area determination; at the same time, the current data processing methods often lack error control mechanisms such as gamma signal water depth attenuation compensation and magnetic susceptibility attitude correction, which limits the detection accuracy and practicability.

[0003] In view of the above problems, it is urgent to construct a rapid detection method for submarine placer deposits that integrates multi-parameter characteristics and has real-time correction capabilities; on the one hand, it is necessary to conduct spatial correlation analysis on radioactive and magnetic data to extract the double-parameter anomaly coincidence area and avoid misjudgment caused by single-parameter anomalies; on the other hand, key technical links such as water depth compensation, dip correction, and anomaly grading need to be introduced to improve the stability of detection data, regional comparability, and the scientificity of target area identification. Therefore, a rapid detection method for submarine placer deposits based on shipborne towed joint measurement is developed to solve the above problems. Summary of the Invention

[0004] Based on the above purpose, the present invention provides a rapid detection method for submarine placer deposits based on shipborne towed joint measurement.

[0005] The rapid detection method for submarine placer deposits based on shipborne towed joint measurement includes the following steps: S1: Connect the towed body integrating a gamma energy spectrum detection component, a magnetic susceptibility detection component, and a pressure-bearing and sealing structure to the shipborne integrated control host through a cable, and adjust the towed body to a preset submarine detection depth; S2: Start the gamma energy spectrum detection component to obtain radioactive gamma total channel count and uranium, thorium, and potassium content data in real time, and at the same time start the magnetic susceptibility detection component to obtain sediment magnetic susceptibility and equipment dip data in real time; S3: Perform water depth pressure compensation correction on the gamma energy spectrum data obtained in S2, and perform dip correction and external magnetic field interference shielding processing on the magnetic susceptibility data; S4: Convert the corrected gamma energy spectrum data into a radioactive anomaly intensity map, and convert the corrected magnetic susceptibility data into a magnetic susceptibility anomaly intensity map. Both are marked with spatial coordinates at a scale of 1:10,000. S5: Perform spatial superposition on the radioactive anomaly intensity map and the magnetic susceptibility anomaly intensity map, extract the overlapping area of the two-parameter anomalies, and combine with a preset threshold to screen out the heavy mineral ore target area. S6: Integrate the coordinates, radioactive intensity, and magnetic susceptibility intensity data of the heavy mineral ore target area into a standardized report.

[0006] Optionally, the specific steps of S1 include: S11: Connect the towing body encapsulated with the integrated gamma energy spectrum detection component, magnetic susceptibility detection component, and pressure-bearing sealing structure to the shipborne integrated control host through a high-modulus polyethylene cable with a preset strength of 20 kN. Directional joints and quick-lock pluggable components are respectively provided at both ends of the cable. S12: Set the diving depth parameter on the shipborne control host, release the cable at a speed of 0.2 m / s through the automatic winch system, and use the pressure sensor and depth gauge integrated in the cable to monitor the current depth data of the towing body in real time until the towing body stably hovers at a preset detection layer 1.5 meters above the seabed and automatically stops paying out the cable. S13: Synchronously start the hydrodynamic stability control unit through the control host. The hydrodynamic stability control unit includes double-wing stabilizing fins and a counterweight adjustment component located at the trailing edge of the towing body, which is used to keep the heading of the towing body stable and the attitude angle less than 2°.

[0007] Optionally, the specific steps of S2 include: S21: Send a start command to the gamma energy spectrum detection component through the shipborne integrated control host. The gamma energy spectrum detection component includes a sodium iodide scintillation detector, a multi-channel analyzer, and a data transmission interface. After the detector is powered on and reaches the working voltage of 750V, collect gamma energy spectrum data at an interval of 0.1 second, and the multi-channel analyzer analyzes the total channel count and the potassium, uranium, and thorium count values corresponding to the energy regions of 1.46 MeV, 1.76 MeV, and 2.61 MeV. S22: Synchronously activate the magnetic susceptibility detection component. The magnetic susceptibility detection component consists of a three-axis low-frequency induction magnetic susceptibility sensor array and a three-dimensional accelerometer. After startup, continuously collect the change of the sediment response signal at a frequency of 1 Hz, and combine with the three-axis attitude angle data measured by the three-dimensional accelerometer to output the volume magnetic susceptibility value and the current device inclination data in real time. S23: All the collected data is real-time transmitted back to the shipborne control host through the data channel in the cable, and the gamma energy spectrum and magnetic susceptibility data streams are synchronously displayed on the control interface in the form of time stamps.

[0008] Optionally, the specific steps of S3 include: S31: Match the gamma energy spectrum data and the radioactive element count data in each energy region collected by the gamma energy spectrum detection component with the water depth information obtained in real time by the pressure sensor integrated with the towed body. According to the hydrostatic pressure parameters corresponding to the water depth, compensate for the count deviation caused by energy attenuation of the gamma signal in the water body to obtain the depth-corrected radioactive gamma energy spectrum data; S32: Combine the original volume magnetic susceptibility data collected by the magnetic susceptibility detection component with the attitude angle data obtained by the triaxial accelerometer. According to the tilt angles of the device in the x-axis and y-axis directions at present, perform geometric attitude correction on the magnetic susceptibility value to eliminate the magnetic response distortion caused by the attitude deviation of the towed body; S33: Call the sea area background magnetic field intensity data recorded by the shipborne control host, perform interference discrimination on the corrected magnetic susceptibility data, and filter out the data exceeding the set magnetic field perturbation threshold range.

[0009] Optionally, the S31 specifically includes: S311: Obtain the original gamma energy spectrum data within every 0.1-second time window by the gamma energy spectrum detection component , and receive the water depth data h of the position where the towed body is located in real time; S312: According to the hydrostatic pressure conditions corresponding to the water depth, combine the energy attenuation characteristics of the water body to gamma rays to compensate the original gamma energy spectrum data. The formula is: , where is the corrected gamma energy spectrum data, represents the exponential compensation factor for signal attenuation of the water body, and the in it is the average attenuation coefficient of the water body to gamma rays, and the value is 0.045; S313: Perform the same depth compensation and correction on the counts of uranium, thorium, and potassium corresponding to all gamma energy regions, and uniformly encode and store the correction results as a structured radioactive energy spectrum data set.

[0010] Optionally, the S32 specifically includes: S321: Obtain the tilt angle data of the current towed body in the x-axis and y-axis directions in real time by the triaxial accelerometer in the magnetic susceptibility detection component, and record them as and respectively, with the unit of radian; S322: Assume that the original volume magnetic susceptibility is , and perform geometric attitude correction on it. The specific formula is: , where is the corrected magnetic susceptibility, is the correction factor, representing the projection ratio of the included angle between the current attitude direction and the gravity direction; S323: Mark the sampling data with attitude angles exceeding 0.35 radians as unstable states, and eliminate the data of the marked part.

[0011] Optionally, the specific steps of S4 include: S41: Perform normalization grid interpolation on the corrected gamma energy spectrum data according to the measuring point position coordinates, and generate a radioactive intensity distribution field in a unified spatial grid with a scale of 1:10,000 using the inverse distance weighted algorithm; and according to the regional background statistical mean and standard deviation , identify the grid areas with gamma intensity values higher than as radioactive anomaly areas, and output a radioactive anomaly intensity map; S42: Perform interpolation on the corrected magnetic susceptibility data according to the spatial coordinates corresponding to the acquisition points, establish a continuous magnetic susceptibility distribution layer using the Kriging spatial interpolation algorithm, and based on the background magnetic susceptibility mean and standard deviation set an anomaly judgment threshold, and identify the grid areas with magnetic susceptibility values higher than as magnetic susceptibility anomaly areas, and output a magnetic susceptibility anomaly intensity map; S43: Perform layer metadata encoding on the two anomaly intensity maps respectively, including sampling time, spatial reference system, interpolation algorithm and anomaly level description, and export them in vector format.

[0012] Optionally, the specific steps of S5 include: S51: Import the radioactive anomaly intensity map and magnetic susceptibility anomaly intensity map generated by S4 into the geological information processing platform, perform reprojection and raster alignment using a unified coordinate system to ensure that the two layers are completely matched in the spatial dimension; S52: Use the layer overlay algorithm to perform pixel-level intersection operation on the two anomaly maps, and extract the overlapping areas that simultaneously meet the radioactive intensity value and magnetic susceptibility value , which is the anomaly overlapping area; S53: Calculate the internal average radioactive intensity value and average magnetic susceptibility value for each anomaly overlapping area respectively, and judge whether the anomaly overlapping area meets the target area screening conditions according to the preset numerical threshold standard, and then extract the heavy sand ore target area.

[0013] Optionally, the specific steps of S53 include: S531: Extract the radioactive intensity value and magnetic susceptibility value for all grid cells in each anomaly overlapping area, with a total of n effective pixels; S532: Calculate the average radioactive intensity value and average magnetic susceptibility value , the formula is: ; ; S533: Call the average regional background radioactivity in S4 and the average magnetic susceptibility , and set the corresponding screening threshold coefficients to 1.3 and 1.2 respectively, and determine whether the following conditions are met: Judgment condition 1, ; Judgment condition 1, ; If both of the above judgment conditions are met at the same time, mark the corresponding abnormal coincidence area as the placer ore target area.

[0014] Optionally, the S6 specifically includes: S61: Extract the spatial unit numbers of the areas that have been screened as placer ore target areas, calculate the boundary center point coordinates for each target area unit, and record the minimum circumscribed rectangle range covered by the target area; S62: Extract the corresponding average radioactivity intensity value and the average magnetic susceptibility intensity value of the target area unit from the layer attribute data, and synchronously record its generation time, coordinate reference system and anomaly level; S63: Organize all target area data into standard structured report entries. Each piece of data includes the target area number, center coordinates, spatial range, radioactivity intensity value, magnetic susceptibility intensity value, anomaly level, data collection time and processing batch number, and output them in the GeoJSON format uniformly; S64: Check and sign and archive the generated standardized report file.

[0015] Advantages of the present invention: In the present invention, by integrating a gamma energy spectrum detection component and a magnetic susceptibility detection component into a shipborne towed body, combined with water depth pressure compensation, attitude angle correction and external magnetic disturbance suppression technologies, high-precision real-time acquisition and correction of gamma signals and magnetic susceptibility data are achieved; through continuous detection under high-stability attitude control near the bottom layer, physical response deviations caused by depth changes, equipment tilting and environmental interference are effectively eliminated.

[0016] In the present invention, by constructing a radioactivity and magnetic susceptibility anomaly intensity map and carrying out spatial coincidence analysis, extracting the placer ore target area based on the double-parameter overlapping area, and establishing an anomaly intensity grading criterion in combination with the regional statistical mean value, rapid and quantitative determination of high-enrichment potential areas is achieved; finally, the target area number, spatial position and physical parameters are output through a standardized structured report, providing clear data support for subsequent operation deployment. Brief description of the drawings

[0017] To more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only those of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0018] Figure 1 Schematic diagram of the rapid detection method for submarine placer minerals in an embodiment of the present invention; Figure 2 Schematic diagram of the data compensation and correction process in an embodiment of the present invention. Detailed implementation manners

[0019] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. At the same time, it should be noted here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments. For some well-known technologies, those skilled in the art can also adopt other alternative methods for implementation; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0020] As Figure 1 - Figure 2 shown, the rapid detection method for submarine placer minerals based on shipborne towed combined measurement includes the following steps: S1: Connect the towed body integrating the gamma energy spectrum detection component, magnetic susceptibility detection component and pressure-bearing sealing structure to the shipborne integrated control host through a cable, and adjust the towed body to the preset submarine detection depth; S2: Start the gamma energy spectrum detection component to obtain the total radioactive gamma channel count and the uranium, thorium, and potassium content data in real time, and at the same time start the magnetic susceptibility detection component to obtain the sediment magnetic susceptibility and the equipment inclination data in real time; S3: Perform water depth pressure compensation and correction on the gamma energy spectrum data obtained in S2, and perform inclination correction and external magnetic field interference shielding processing on the magnetic susceptibility data; S4: Convert the corrected gamma energy spectrum data into a radioactive anomaly intensity map, and convert the corrected magnetic susceptibility data into a magnetic susceptibility anomaly intensity map, both of which are marked with spatial coordinates at a scale of 1:10000; S5: Perform spatial superposition on the radioactive anomaly intensity map and the magnetic susceptibility anomaly intensity map, extract the double-parameter anomaly coincidence area, and combine the preset threshold to screen out the placer mineral target area; S6: Integrate the coordinates, radioactive intensity, and magnetic susceptibility intensity data of the placer mineral target area into a standardized report.

[0021] S1 specifically includes: S11: Connect the towing body encapsulated with an integrated gamma energy spectrum detection component, a magnetic susceptibility detection component, and a pressure-bearing sealing structure to the shipborne integrated control host through a high-modulus polyethylene cable with a preset strength of 20 kN. Directional joints and quick-lock plug-in connectors are respectively provided at both ends of the cable to ensure the stability and reliability of power supply and data communication; S12: Set the diving depth parameter on the shipborne control host, release the cable at a speed of 0.2 m / s through the automatic winch system, and use the pressure sensor and depth gauge integrated in the cable to monitor the current depth data of the towing body in real time until the towing body stably hovers at a preset detection layer 1.5 meters above the seabed and automatically stops paying out; S13: Synchronously start the hydrodynamic stability control unit through the control host. The hydrodynamic stability control unit includes double-wing stabilizing fins and a counterweight adjustment component located at the trailing edge of the towing body, which are used to keep the towing body's heading stable and the attitude angle less than 2°, ensuring the accuracy of detection data acquisition; The above steps use a high-strength cable and a quick-connector structure to connect the towing body and the control host to ensure the stable transmission of electrical signals in the deep-sea environment; Combine the automatic winch and the real-time depth monitoring mechanism to achieve precise control of the detection depth of the towing body, and maintain the attitude stability of the towing body through the stabilizing fins and counterweight adjustment, effectively improving the measurement accuracy and operation safety of near-bottom placer mining detection on the seabed.

[0022] S2 specifically includes: S21: Send a start command to the gamma energy spectrum detection component through the shipborne integrated control host. The gamma energy spectrum detection component includes a high-sensitivity sodium iodide (NaI) scintillation detector, a multi-channel analyzer (MCA), and a data transmission interface; After the detector is powered on and reaches the working voltage of 750V, collect gamma energy spectrum data at 0.1-second time intervals, and the multi-channel analyzer analyzes the total channel count and the potassium, uranium, and thorium count values corresponding to the energy regions of 1.46 MeV, 1.76 MeV, and 2.61 MeV; S22: Synchronously activate the magnetic susceptibility detection component. The magnetic susceptibility detection component consists of a three-axis low-frequency induction magnetic susceptibility sensor array and a three-dimensional accelerometer; After starting, continuously collect the changes in the sediment response signal at a frequency of 1 Hz, and combine the three-axis attitude angle data measured by the three-dimensional accelerometer to output the volume magnetic susceptibility value and the current device inclination data in real time; S23: All the collected data is transmitted back to the shipborne control host in real time through the data channel in the cable, and the gamma energy spectrum and magnetic susceptibility data streams are synchronously displayed on the control interface in timestamp mode for subsequent calibration processing; The above steps ensure the high-timeliness and high-precision acquisition of radioactive element and magnetic characteristic data through the synchronous start and high-frequency acquisition of the high-sensitivity gamma energy spectrum detection component and the low-frequency three-axis magnetic susceptibility sensor. At the same time, by integrating the attitude angle calibration information, it provides a complete raw data basis for subsequent calibration and anomaly identification, significantly improving the recognition accuracy of multi-parameter characteristics of placer mining.

[0023] S3 specifically includes: S31: Match the gamma energy spectrum data collected by the gamma energy spectrum detection component and the radioactive element count data in each energy region with the water depth information obtained in real time by the pressure sensor integrated with the drag body. According to the hydrostatic pressure parameter corresponding to the water depth, compensate for the count deviation caused by the energy attenuation of the gamma signal in the water body to obtain the depth-corrected radioactive gamma energy spectrum data; S32: Combine the original volume magnetic susceptibility data collected by the magnetic susceptibility detection component with the attitude angle data obtained by the triaxial accelerometer. According to the tilt angles of the device in the x-axis and y-axis directions at present, perform geometric attitude correction on the magnetic susceptibility value to eliminate the magnetic response distortion caused by the attitude deviation of the drag body; S33: Call the sea area background magnetic field intensity data recorded by the shipborne control host, perform interference discrimination on the corrected magnetic susceptibility data, and filter out the data exceeding the set magnetic field perturbation threshold range, so as to eliminate the abnormal data points that may be affected by external magnetic field perturbation and retain the stable data for subsequent anomaly analysis; The above steps significantly improve the quantitative consistency of the gamma signal at different detection depths by introducing a depth correction mechanism. At the same time, through tilt angle compensation and background magnetic field interference shielding operations, the errors of the magnetic susceptibility data caused by attitude deviation and environmental magnetic interference are significantly reduced, effectively enhancing the reliability of the detection data and the subsequent anomaly recognition accuracy.

[0024] S31 specifically includes: S311: Obtain the original gamma energy spectrum data within every 0.1-second time window by the gamma energy spectrum detection component , and receive in real time the water depth data h (unit: meter) of the position where the drag body is located, which is converted by the pressure sensor built in the pressure-bearing sealed structure; The water depth conversion formula is: , where h is the water depth (unit: meter); P is the hydrostatic pressure (unit: Pa), measured by the pressure sensor on the drag body; is the seawater density, with a value of ; g is the acceleration due to gravity, with a value of ; S312: Compensate the original gamma energy spectrum data according to the hydrostatic pressure condition corresponding to the water depth, combined with the energy attenuation characteristics of gamma rays in the water body. The formula is: , where is the corrected gamma energy spectrum data, represents the exponential compensation factor for signal attenuation in the water body, and the in it is the average attenuation coefficient of gamma rays in the water body, with a value of 0.045; S313: The uranium, thorium and potassium counts corresponding to all gamma energy zones are corrected according to the same depth compensation, and the correction results are uniformly encoded and stored as a structured radioactive energy spectrum data set for subsequent anomaly map generation and processing. By introducing water depth information into the gamma signal compensation calculation, the signal attenuation effect caused by the absorption of high-energy particles by seawater is restored, which significantly improves the lateral comparability of radioactive data under different depth measurement conditions, and provides a reliable physical basis for the spatial anomaly identification of heavy placer targets.

[0025] S32 specifically includes: S321: The three-axis accelerometer in the magnetic susceptibility detection assembly obtains the inclination angle data of the current towed body in the x-axis and y-axis directions in real time, which are recorded as and , in radians, represents the tilt offset relative to the vertical direction; S322: Assume that the original volume susceptibility is , and perform geometric posture correction on it. The specific formula is: ,in, is the corrected magnetic susceptibility, is the correction factor, which represents the angle projection ratio between the current attitude direction and the gravity direction; S323: The attitude angle exceeds 0.35 radians (approx. ) is marked as an unstable state, and the data of the marked part is discarded to avoid the influence of attitude instability on the accuracy of magnetic susceptibility, and the remaining correction data is used for the subsequent generation of magnetic susceptibility anomaly map; the above steps can effectively offset the measurement errors caused by yaw and pitch of the towed body during the detection process by vector synthesis correction of the magnetic susceptibility measurement value based on the three-axis attitude angle, ensure the spatial consistency between the magnetic susceptibility anomaly characteristics and the real geological structure, and provide a high-confidence physical parameter basis for the identification of heavy placer targets.

[0026] S4 specifically includes: S41: The corrected gamma spectrum data are normalized and interpolated according to the coordinates of the measuring point, and the inverse distance weighted (IDW) algorithm is used to generate the radioactivity intensity distribution field in a unified spatial grid at a scale of 1:10000; and the mean value is calculated based on the regional background statistics. With standard deviation , set the gamma intensity value above The grid area is marked as the radioactive anomaly area, and the radioactive anomaly intensity map is output; S42: The corrected magnetic susceptibility data are interpolated according to the spatial coordinates corresponding to the acquisition points, and the Kriging spatial interpolation algorithm is used to establish a continuous magnetic susceptibility distribution layer, and based on the background magnetic susceptibility mean and standard deviation Set the abnormal judgment threshold, and mark the grid areas with magnetic susceptibility values higher than as magnetic susceptibility abnormal areas, and output the magnetic susceptibility abnormal intensity map; S43: Encode the layer metadata for the two abnormal intensity maps respectively, including sampling time, spatial reference system, interpolation algorithm and abnormal level description, and export them in vector format for subsequent spatial overlay analysis process; Through the construction of gamma and magnetic susceptibility abnormal maps based on the spatial interpolation algorithm, the above steps can effectively realize the spatial quantitative expression of radioactive and magnetic abnormal areas, and significantly improve the accuracy and engineering practicability of target area identification in subsequent multi-parameter fusion analysis.

[0027] S5 specifically includes: S51: Import the radioactive abnormal intensity map and magnetic susceptibility abnormal intensity map generated in S4 into the geological information processing platform, and perform reprojection and raster alignment using the unified coordinate system (WGS84 / UTMZone50N) to ensure that the two layers are completely matched in the spatial dimension; S52: Use the layer overlay algorithm to perform pixel-level intersection operation on the two abnormal maps, and extract the overlapping areas that simultaneously meet the radioactive intensity value and magnetic susceptibility value , which is the abnormal overlapping area; S53: Calculate the internal average radioactive intensity value and average magnetic susceptibility value for each abnormal overlapping area respectively, and judge whether the abnormal overlapping area meets the target area screening conditions according to the preset numerical threshold standard, and then extract the heavy sand ore target area; Through the standardized spatial alignment and layer overlay method, the above steps realize the automatic extraction of the double-parameter significant abnormal areas, and complete the candidate area screening in combination with the mean judgment logic, effectively improving the efficiency and accuracy of target area extraction, and providing accurate support for the rapid discrimination of heavy sand ore targets.

[0028] S53 specifically includes: S531: Extract the radioactive intensity value and magnetic susceptibility value for all grid cells in each abnormal overlapping area, with a total of n effective pixels; S532: Calculate the average radioactive intensity value and average magnetic susceptibility value of the abnormal overlapping area, and the formula is: ; ; S533: Call the regional background radioactive mean and magnetic susceptibility mean in S4, and set the corresponding screening threshold coefficients to 1.3 and 1.2 respectively, and judge whether the following conditions are met: Judgment condition 1, ; Judgment condition 1 ; If the above two judgment conditions are satisfied simultaneously, the corresponding abnormal coincidence area is marked as the placer target area; by averaging the multi-point data in the candidate area and comparing it with the set threshold standard, the above steps can achieve high-precision screening of the placer target area while maintaining the spatial resolution, avoiding local extreme value interference, and improving the stability and geological credibility of the recognition results.

[0029] S6 specifically includes: S61: Extract the spatial unit numbers that have been screened as placer target areas, calculate the boundary center point coordinates (expressed in latitude and longitude format) for each target area unit, and record the minimum circumscribed rectangle range covered by the target area; S62: Extract the average radioactive intensity value corresponding to the target area unit from the layer attribute data and the average magnetic susceptibility intensity value , and synchronously record its generation time, coordinate reference system (such as WGS 84) and anomaly level; The grading rules for the anomaly level are as follows: (1) Radioactive intensity anomaly level division: Medium-level anomaly: ; High-level anomaly: ; Extremely high-level anomaly: ; (2) Magnetic susceptibility anomaly level division: Medium-level anomaly: ; High-level anomaly: ; Extremely high-level anomaly: ; Grade evaluation principle: If the radioactive and magnetic susceptibility grades are the same, then this grade is the final anomaly grade of the target area; if the grades of the two are different, then the lower grade is the final evaluation grade to control the risk of misjudgment.

[0030] S63: Organize all target area data into standard structured report entries. Each piece of data includes the target area number, center coordinates, spatial range, radioactive intensity value, magnetic susceptibility intensity value, anomaly level, data collection time, and processing batch number, and output them in the GeoJSON format uniformly, supporting visual loading and remote platform calls; S64: Verify and sign and archive the generated standardized report file to ensure data integrity and uniqueness; by structuring and integrating spatial coordinates, physical anomaly indicators, and metadata information into a standardized format report, the above steps not only achieve a unified and standardized expression of the heavy sand ore target area data, but also provide a reliable data foundation and high-efficiency system compatibility for subsequent remote analysis, targeted sampling, and result archiving.

[0031] The present invention covers any alternatives, modifications, equivalent methods, and solutions made within the spirit and scope of the present invention. For the public to have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, and those skilled in the art can fully understand the present invention without these detailed descriptions. Additionally, well-known methods, processes, procedures, components, and circuits, etc., are not described in detail to avoid unnecessary confusion to the essence of the present invention.

[0032] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A rapid detection method for submarine placer minerals based on shipborne towed combined measurement, characterized in that, It includes the following steps: S1: Connect the towed body integrating a gamma energy spectrum detection component, a magnetic susceptibility detection component, and a pressure-bearing and sealing structure to the shipborne integrated control host through a cable, and adjust the towed body to a preset seabed detection depth; S2: Start the gamma energy spectrum detection component to obtain the total radioactive gamma channel count and the uranium, thorium, and potassium content data in real time, and at the same time start the magnetic susceptibility detection component to obtain the sediment magnetic susceptibility and the equipment inclination data in real time; S3: Perform water depth pressure compensation and correction on the gamma energy spectrum data obtained in S2, and perform inclination correction and external magnetic field interference shielding processing on the magnetic susceptibility data; S4: Convert the corrected gamma energy spectrum data into a radioactive anomaly intensity map, and convert the corrected magnetic susceptibility data into a magnetic susceptibility anomaly intensity map, both of which are marked with spatial coordinates at a scale of 1:10,000; S5: Perform spatial superposition on the radioactive anomaly intensity map and the magnetic susceptibility anomaly intensity map, extract the double-parameter anomaly coincidence area, and combine with a preset threshold to screen out the heavy sand ore target area; S6: Integrate the coordinates, radioactive intensity, and magnetic susceptibility intensity data of the heavy sand ore target area into a standardized report.

2. The rapid detection method of submarine placer ore based on shipborne towed combined measurement according to claim 1, wherein The specific content of S1 includes: S11: Connect the towed body encapsulated with a gamma energy spectrum detection component, a magnetic susceptibility detection component, and a pressure-bearing and sealing structure to the shipborne integrated control host through a high-modulus polyethylene cable with a preset strength of 20 kN. Directional joints and quick-lock pluggable components are respectively provided at both ends of the cable; S12: Set the diving depth parameter on the shipborne control host, release the cable at a speed of 0.2 m / s through the automatic winch system, and real-time monitor the current depth data of the towed body through the pressure sensor and depth gauge integrated in the cable until the towed body stably hovers at a preset detection layer 1.5 meters away from the seabed, and then automatically stop the winching; S13: Synchronously start the hydrodynamic stability control unit through the control host. The hydrodynamic stability control unit includes double-wing stabilizing fins and a counterweight adjustment component located at the trailing edge of the towed body, which is used to keep the heading of the towed body stable and the attitude angle less than 2°.

3. The rapid detection method for submarine placer ore based on shipborne towed combined measurement according to claim 1, wherein, The specific content of S2 includes: S21: Send a start command to the gamma energy spectrum detection component through the shipborne integrated control host. The gamma energy spectrum detection component includes a sodium iodide scintillation detector, a multi-channel analyzer, and a data transmission interface; after the detector is powered on and reaches the working voltage of 750 V, collect the gamma energy spectrum data at an interval of 0.1 s, and the multi-channel analyzer analyzes the total channel count and the potassium, uranium, and thorium count values corresponding to the energy regions of 1.46 MeV, 1.76 MeV, and 2.61 MeV; S22: Synchronously activate the magnetic susceptibility detection component. The magnetic susceptibility detection component is composed of a three-axis low-frequency induction magnetic susceptibility sensor array and a three-dimensional accelerometer; after starting, continuously collect the sediment response signal changes at a frequency of 1 Hz, and combine with the three-axis attitude angle data measured by the three-dimensional accelerometer to output the volume magnetic susceptibility value and the current equipment inclination data in real time; S23: All the collected data is real-time transmitted back to the shipborne control host through the data channel in the cable, and the gamma energy spectrum and magnetic susceptibility data streams are synchronously displayed on the control interface in the form of time stamps.

4. The rapid detection method for submarine placer ore based on shipborne towed combined measurement according to claim 1, wherein The specific content of S3 includes: S31: matching the gamma spectrum data and radioactive element counting data in each energy zone collected by the gamma spectrum detection component with the water depth information acquired in real time by the pressure sensor integrated in the towed body, compensating for the counting deviation of the gamma signal caused by energy attenuation in the water body according to the hydrostatic pressure parameter corresponding to the water depth, and obtaining the radioactive gamma spectrum data corrected by depth; S32: combining the original volume magnetic susceptibility data collected by the magnetic susceptibility detection component with the attitude angle data obtained by the three-axis accelerometer, and performing geometric attitude correction on the magnetic susceptibility value according to the current inclination angle of the device in the x-axis and y-axis directions to eliminate the magnetic response distortion caused by the attitude deviation of the towed body; S33: calling the background magnetic field strength data of the sea area recorded by the shipboard control host, performing interference discrimination on the corrected magnetic susceptibility data, and filtering out the data exceeding the set magnetic field disturbance threshold range.

5. The rapid detection method of submarine placer ore based on shipborne towed combined measurement according to claim 4, characterized in that, The S31 specifically includes: S311: Obtain the original gamma energy spectrum data within every 0.1-second time window by the gamma energy spectrum detection component , and receive the water depth data h of the position where the towed body is located in real time; S312: Compensate the original gamma energy spectrum data according to the hydrostatic pressure conditions corresponding to the water depth and combining with the energy attenuation characteristics of the water body to gamma rays. The formula is: , where is the corrected gamma energy spectrum data, represents the exponential compensation factor for signal attenuation by the water body, and in it is the average attenuation coefficient of the water body to gamma rays, and the value is 0.045; S313: The counts of uranium, thorium and potassium corresponding to all gamma energy regions are corrected according to the same depth compensation, and the correction results are uniformly encoded and stored as a structured radioactivity spectrum data set.

6. The rapid detection method of submarine placer ore based on shipborne towed combined measurement according to claim 4, characterized in that The S32 specifically includes: S321: The triaxial accelerometer in the magnetic susceptibility detection component obtains the tilt angle data of the current towed body in the x-axis and y-axis directions in real time, denoted as and , with the unit of radian; S322: Let the original volume magnetic susceptibility be , and perform geometric attitude correction on it. The specific formula is: , where is the corrected magnetic susceptibility, is the correction factor, representing the angle projection ratio between the current attitude direction and the gravity direction; S323: Mark the sampling data with a posture angle exceeding 0.35 radians as an unstable state, and remove the data of the marked part.

7. The rapid detection method for submarine placer ore based on shipborne towed combined measurement according to claim 1, characterized in that The S4 specifically includes: S41: Normalize and interpolate the corrected gamma energy spectrum data according to the measuring point position coordinates, and generate a radioactive intensity distribution field within a unified spatial grid of 1:10,000 scale using the inverse distance weighted algorithm; and based on the statistical mean and standard deviation , identify the grid areas with gamma intensity values higher than as radioactive anomaly areas and output a radioactive anomaly intensity map; S42: Interpolate the corrected magnetic susceptibility data according to the spatial coordinates corresponding to the acquisition points, use the Kriging spatial interpolation algorithm to establish a continuous magnetic susceptibility distribution layer, and based on the background magnetic susceptibility mean value and standard deviation set the anomaly judgment threshold, and mark the grid area where the magnetic susceptibility value is higher than as the magnetic susceptibility anomaly area, and output the magnetic susceptibility anomaly intensity map; S43: Encode the layer metadata of the two anomaly intensity maps, including sampling time, spatial reference system, interpolation algorithm and anomaly level description, and export them in vector format.

8. The rapid detection method of submarine placer ore based on shipborne towed combined measurement according to claim 1, characterized in that The S5 specifically includes: S51: Import the radioactivity anomaly intensity map and magnetic susceptibility anomaly intensity map generated by S4 into the geological information processing platform, and use a unified coordinate system for reprojection and grid alignment to ensure that the two layers are completely matched in the spatial dimension; S52: Use the layer overlay algorithm to perform pixel-level intersection operations on two anomaly maps, and extract the overlapping region that simultaneously satisfies the radioactive intensity value and the magnetic susceptibility value The overlapping region is the anomaly overlapping region; S53: Calculate the internal average radioactivity intensity value and the average magnetic susceptibility value of each abnormal overlap area respectively, and judge whether the abnormal overlap area meets the target area screening conditions according to the preset numerical threshold standard, so as to extract the heavy placer target area.

9. The rapid detection method of submarine placer ore based on shipborne towed combined measurement according to claim 8, characterized in that, The S53 specifically includes: S531: Extract the radioactive intensity value and magnetic susceptibility value for each grid cell in all abnormal coincidence regions, with a total of n valid pixels. and magnetic susceptibility value , for a total of n valid pixels; S532: Calculate the average radioactive intensity value of the abnormal coincidence region and the average magnetic susceptibility value , the formula is: ; ; S533: Call the regional background radioactivity mean value in S4 and the magnetic susceptibility mean value , and set the corresponding screening threshold coefficients to 1.3 and 1.2 respectively, and determine whether the following conditions are met: Judgment condition 1, ; Judgment condition 1, ; If the above two judgment conditions are met at the same time, the corresponding abnormal overlap area will be marked as a heavy placer target area.

10. The rapid detection method for submarine placer ore based on shipborne towed combined measurement according to claim 9, wherein The S6 specifically includes: S61: extracting the spatial unit numbers that have been screened as heavy placer target areas, calculating the coordinates of the boundary center point of each target area unit, and recording the minimum circumscribed rectangular range covered by the target area; S62: Extract the average radioactive intensity value corresponding to the target area unit from the layer attribute data and the average magnetic susceptibility intensity value , and synchronously record its generation time, coordinate reference system, and anomaly level; S63: All target area data are organized into standard structured report items. Each data item includes the target area number, center coordinates, spatial range, radioactivity intensity value, magnetic susceptibility intensity value, anomaly level, data collection time and processing batch number, and is uniformly output in GeoJSON format; S64: Verify and sign the generated standardized report file for archiving.

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