A method for delineating abnormal halos in ground-based gamma-ray spectrum measurement

Abstract

The present invention specifically relates to a method for delineating abnormal halos in ground gamma spectrum measurement work, comprising the following steps: using multivariate information fusion technology to design a gamma spectrum measurement route based on a conventional gamma spectrum measurement route; carrying out measurement work of the gamma spectrum measurement route in a work area according to the gamma spectrum measurement route; conducting on-site verification of known radioactive anomaly information that has not been discovered to check for leaks and fill in the gaps; further screening out radioactive anomalies and conducting on-site repeated inspections and measurements and mineralization point inspections; processing and analyzing gamma spectrum measurement data and combining the inspection results to delineate abnormal halos; comprehensively sorting abnormal halos; and finally combining other geological information to conduct comprehensive long-term predictions. The method for delineating abnormal halos in ground gamma spectrum measurement work of the present invention optimizes and improves the efficiency of delineating abnormal halos.

Description

Technical Field

[0001] The invention relates to the technical field of uranium ore exploration and geophysical prospecting, and in particular to a method for delineating abnormal halos in ground gamma spectrum measurement work. Background Art

[0002] Ground gamma spectroscopy is a radioactive geophysical exploration method that uses a portable gamma spectrometer to measure the content of uranium, thorium and potassium in the ground target at a certain scale to explore minerals and solve geological problems. Ground gamma spectroscopy uses the characteristics of significant differences in the energy of gamma rays released by uranium, thorium and potassium elements. The gamma ray signal of the target is collected by the gamma spectrometer, converted and processed, and the corresponding gamma ray count rate of various energies and the corresponding nuclide content are calculated.

[0003] Compared with natural gamma measurement, which can only reflect the total content of radionuclides in the target body but cannot distinguish the types of radionuclides contained in the target body, ground gamma spectrum measurement can not only understand the level of total radioactivity of the target body, but also quantitatively measure the content of different nuclides. Therefore, ground gamma spectrum measurement is more practical and can solve more geological problems. It has been widely used in ground, aviation, underground and other radioactivity measurements.

[0004] Usually, ground gamma spectral area measurement is affected by the grid size and manual operation, and some small-scale anomalies will always be missed more or less. In addition, in general, the distance between survey lines is much larger than the point distance, and it is easier to miss small-scale anomalies in the vertical survey line direction. However, hydrothermal uranium deposits are often small in scale and mostly blind ore bodies. There are a large number of small-scale anomalies on the surface of uranium mines that extend less than 500m or even less than 100m. In the investigation and evaluation stage of hydrothermal uranium deposits, the most commonly used method is the ground gamma spectral area measurement with a scale of 1:50000, with a grid size of 500m×(50~100)m, which is easy to miss small-scale anomalies. Summary of the invention

[0005] Based on this, it is necessary to provide a method for delineating abnormal halos in ground gamma energy spectrum area measurement work in order to address the problem that anomalies are easily missed in the existing ground gamma energy spectrum area measurement. This method improves the ground gamma energy spectrum area measurement method from the aspects of route design, measurement method and leak detection, takes small-scale anomalies into account to the greatest extent, accurately delineates the distribution range of abnormal halos, and effectively improves the efficiency of delineating abnormal halos in ground gamma energy spectrum area measurement work.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A method for delineating abnormal halos in ground gamma spectrum area measurement work comprises the following steps:

[0008] Step 1: Conduct comprehensive analysis and research based on the existing radioactive data in the work area, extract the existing radioactive anomaly information in the work area from the existing radioactive data in the work area, screen out the important radioactive anomaly information in the work area based on the existing radioactive anomaly information in the work area, and conduct field surveys in the sections of the work area where there is important radioactive anomaly information;

[0009] Step 2: Based on the comprehensive analysis and research and exploration of step 1, combined with the work stage, work area and geological complexity, and in accordance with the requirements of ground gamma spectrum measurement specifications, select the gamma spectrum measurement route network; conduct a comprehensive score ranking of each section of the work area, and design a gamma spectrum measurement route based on the conventional gamma spectrum measurement route according to the comprehensive score ranking results of each section of the work area;

[0010] Step 3: According to the gamma spectrum measurement route designed in step 2, the gamma spectrum measurement route is measured in the work area in accordance with the ground gamma spectrum measurement specification requirements. During the measurement of the gamma spectrum measurement route, the gamma spectrometer measurement data is continuously turned on;

[0011] Step 4: Conduct on-site verification of the important radioactive anomaly information screened out in step 1 and the known radioactive anomaly information not found in step 3. If radioactive anomalies are confirmed, the gamma spectrum measurement short line is promptly supplemented to conduct gamma spectrum measurement route measurement to complete the missing check;

[0012] Step 5: Comprehensively analyze the gamma spectrum measurement data of steps 3 and 4 and the gamma spectrum measurement verification results of step 4, further screen out radioactive anomalies with considerable radioactive intensity or distribution scale, and conduct repeated field inspections and mineralization point inspections;

[0013] Step 6: Based on the gamma spectrum measurement data of steps 3, 4 and 5, draw a plane section view and a series of contour maps, and then combine the inspection results of step 5 to circle the abnormal halos; comprehensively sort the abnormal halos and make a comprehensive prospect prediction in combination with other geological information.

[0014] Furthermore, in step 1, the existing radioactive results data include existing uranium exploration data, aerial radioactive work data, ground radioactive work data, surface radioactive anomaly point belt information and geophysical and geochemical exploration results data; the existing radioactive anomaly information includes existing radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration anomaly information.

[0015] Furthermore, in step 2, the elements of the multivariate information of each section of the working area are fused and extracted, and the fused and extracted elements of each section of the working area are scored. The arithmetic sum of the scores of the fused and extracted elements of each section of the working area is the comprehensive score of each section of the working area. The comprehensive scores of each section of the working area are ranked, and a gamma spectrum measurement route is designed based on the conventional gamma spectrum measurement route according to the ranking results of the comprehensive scores of each section of the working area.

[0016] Furthermore, the multivariate information includes known radioactive anomaly information and exploration status information, and the known radioactive anomaly information includes known radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration radioactive anomaly information. The following elements are extracted from the known radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration radioactive anomaly information: radioactive intensity, distribution scale, mineralization type and distribution morphology; the following elements are extracted from the exploration status information: work degree, work stage, work method and exploration results, and each section of the work area is comprehensively scored according to Table 1:

[0017] Table 1 Scoring table of elements extracted by multivariate information fusion in each section of the work area

[0018]

[0019]

[0020]

[0021] Furthermore, in step 2, the design of the gamma spectrum measurement route should take into account the known radioactive anomaly information and highlight the key points. For sections with a comprehensive score higher than 30 points, the gamma spectrum route grid spacing is reduced on the basis of the conventional gamma spectrum measurement route grid spacing. For sections with a comprehensive score lower than 10 points, the gamma spectrum route grid spacing is expanded on the basis of the conventional gamma spectrum measurement route grid spacing. The adjustment range of the gamma spectrum route grid spacing shall not exceed 1 / 2 of the conventional gamma spectrum measurement route grid spacing. If some important radioactive anomaly information is encountered, the conventional gamma spectrum measurement route cannot be taken into account or the extension range of the radioactive anomaly of two adjacent gamma spectrum measurement routes is suddenly reduced, an unconventional gamma spectrum measurement short line shall be added.

[0022] Furthermore, in step 3, during the measurement of the gamma spectrum measurement route, when the gamma spectrum measurement route deviates from the radioactive anomaly point within 100m, the gamma spectrum measurement route is measured near the radioactive anomaly point within the deviation range of the gamma spectrum measurement route required by the ground gamma spectrum measurement specification; when the gamma spectrum measurement route deviates from the important radioactive anomaly point by more than 100m, refer to step 2 to add an encrypted gamma spectrum measurement short line to measure the gamma spectrum measurement route; the gamma spectrometer measurement data is continuously turned on during the travel between measurement points. If it is found that the data between the measurement points is abnormally increased, an encrypted fixed-point gamma spectrum measurement is performed, and the encrypted point distance is controlled at 50m or 20m according to the radioactive anomaly range and the radioactivity intensity; at least one set of stable data is measured at each measurement point, and the measurement time for each measurement is the time required by the gamma spectrometer specification.

[0023] Furthermore, in step 4, the known radioactive anomaly information not found in step 3 is verified on the spot to find out the omissions; then, the measurement data of the gamma spectrum measurement route in step 3 is preliminarily processed to understand the intensity and distribution of the radioactive anomalies found in the measurement process of the ground gamma spectrum measurement route, and then compared with the important radioactive anomaly information identified and screened out in step 1 to screen out radioactive anomalies with considerable radioactive intensity or distribution scale, and at the same time, the important radioactive anomalies and geophysical and chemical anomalies that were not found in the measurement process of the gamma spectrum measurement route are marked, and an encrypted gamma spectrum measurement short line is added to measure the gamma spectrum measurement route to avoid the omission of key radioactive anomalies.

[0024] Furthermore, in step 5, during the repeated on-site inspection and measurement of radioactive anomalies and the inspection of mineralized points, the scale of mineralization, type of mineralization, type of alteration, lithology and surrounding rock characteristics are recorded in detail, and a preliminary evaluation is conducted to screen out important radioactive anomaly points and belts; for some small-scale but promising radioactive anomalies, they are appropriately magnified during the process of anomaly halo identification.

[0025] Furthermore, in step 6, the gamma spectrum measurement data of steps 3, 4 and 5 are processed and analyzed in detail, and a plane profile and a contour map of the total amount of uranium, thorium, potassium and the total amount are drawn. Then, in combination with the distribution characteristics of the total amount of uranium, thorium, potassium and the inspection results of step 5, the abnormal area with the content of uranium, thorium and potassium being greater than or equal to 3 times the average value of the geological background is circled; the abnormal area whose abnormal range is controlled by the same layer or structure and extends more than 20m or has a total length of more than 40m is circled as an abnormal halo; the properties of the abnormal halo are comprehensively analyzed and comprehensively ranked according to the advantages of the properties of the abnormal halo; and a comprehensive ranking is performed on the basis of the comprehensive ranking of the abnormal halo. According to the prospect prediction, the geological body, structure, existing radioactive results data, the consistency degree of multivariate information with the anomaly halo and other attributes of the anomaly halo are comprehensively classified. The sections with good anomaly display, very favorable mineralization conditions, high consistency of multivariate information, discovered mineral points or industrial mineralization, and good prospecting prospects are predicted as Class I prospecting areas; the sections with relatively good anomaly display, favorable mineralization conditions, high consistency of multivariate information, discovered mineral points or mineralization, and good prospecting prospects are predicted as Class II prospecting areas; the sections with relatively good anomaly display, relatively favorable mineralization conditions, general consistency of multivariate information, unclear mineralization, and unclear prospecting prospects are predicted as Class III prospecting areas.

[0026] Furthermore, the attributes of the anomaly halo include size, anomaly strength, degree of clarity of control factors, degree of correlation of anomaly types and degree of consistency of multivariate information.

[0027] Beneficial technical effects of the present invention:

[0028] The method for delineating abnormal halos in ground gamma-ray spectrum measurement work provided by the present invention optimizes route design by fusing multivariate information of preliminary data, making the measurement work more targeted. In the actual measurement process, important anomalies can be taken into account more comprehensively, while continuous monitoring between points is carried out, and a link for checking and filling missed anomalies is added. These optimizations and improvements further improve the efficiency of delineating abnormal halos, and subsequent inspections and comprehensive sorting clarify the possible potential of abnormal halos, ultimately achieving the purpose of quickly guiding uranium mine exploration. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below with reference to the embodiments.

[0030] Example 1

[0031] A number of abnormal uranium mineralization information has been found in a certain area, which shows that it may have good hydrothermal uranium mineralization prospects. Therefore, a ground gamma spectrum measurement with a scale of 1:50000 is carried out in a certain area as a working area, and the method for delineating abnormal halos in the ground gamma spectrum measurement with a scale of 1:50000 in a certain area is used as an example to describe the present invention in detail.

[0032] The method for delineating abnormal halos in ground-based gamma-ray spectrum measurement work at a scale of 1:50000 in a certain area includes the following steps:

[0033] Step 1: Fully collect and organize the existing radioactive results data of a certain area, conduct comprehensive analysis and research based on the existing radioactive results data of a certain area, extract the existing radioactive anomaly information of a certain area from the existing radioactive results data of a certain area, screen out the important radioactive anomaly information in a certain area based on the existing radioactive anomaly information of a certain area, and conduct field surveys in the A section and B section where there is important radioactive anomaly information in a certain area, so as to preliminarily understand the radioactive anomaly situation in a certain area. There are radioactive anomaly points 7-104 and 85-3 in the A section, and radioactive anomaly points 7-101, 7-6 and 4-7 in the B section.

[0034] The existing radioactive results data include existing uranium exploration data, aerial radioactive work data, ground radioactive work data, surface radioactive anomaly point and belt information, and geophysical and geochemical exploration results data; the existing radioactive anomaly information includes existing radioactive anomaly point and belt information, ground radioactive anomaly information, aerial radioactive anomaly information, and geophysical and geochemical exploration anomaly information.

[0035] Step 2: According to the comprehensive analysis and investigation of step 1, combined with the work stage, work area and geological complexity, and in accordance with the requirements of ground gamma spectrum measurement specifications, select a gamma spectrum measurement route with a grid size of 500m×100m; fuse and extract the elements of the multivariate information of each section in a certain area, score the fused and extracted elements of each section in a certain area, and calculate the arithmetic sum of the scores of the fused and extracted elements of each section in a certain area as the comprehensive score of each section in a certain area, rank the comprehensive scores of each section in a certain area, and design a gamma spectrum measurement route based on the conventional gamma spectrum measurement route according to the ranking results of the comprehensive scores of each section in a certain area.

[0036] The multivariate information includes known radioactive anomaly information and exploration status information, and the known radioactive anomaly information includes known radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration radioactive anomaly information. The following elements are extracted from the known radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration radioactive anomaly information: radioactive intensity, distribution scale, mineralization type and distribution morphology; the following elements are extracted from the exploration status information: work degree, work stage, work method and exploration results, and comprehensive scores are given to each section of a certain area according to Table 1:

[0037] Table 2 Score table of elements extracted by multivariate information fusion in each section of a certain region

[0038]

[0039]

[0040]

[0041] When designing the gamma spectrum measurement route, known radioactive anomaly information should be taken into consideration and key points should be highlighted. For sections with a comprehensive score higher than 30 points, the grid spacing of the gamma spectrum measurement route should be reduced on the basis of the grid spacing of the conventional gamma spectrum measurement route. For sections with a comprehensive score lower than 10 points, the grid spacing of the gamma spectrum measurement route should be expanded on the basis of the grid spacing of the conventional gamma spectrum measurement route. The adjustment range of the grid spacing of the gamma spectrum measurement route shall not exceed 1 / 2 of the grid spacing of the conventional gamma spectrum measurement route. If some known important radioactive anomaly information is encountered and the conventional gamma spectrum measurement route cannot be taken into consideration or the extension range of the radioactive anomaly of two adjacent gamma spectrum measurement routes is suddenly reduced, an unconventional gamma spectrum measurement short line shall be added.

[0042] Referring to Table 3, when designing the gamma spectrum measurement route for a certain area, Section C, Section D and Section E are important sections with high scores, and the grid line spacing of the gamma spectrum measurement route is reduced to 300m on the basis of the grid line spacing of the conventional gamma spectrum measurement route; the Quaternary riverbed is a non-important section with low scores, and the grid line spacing of the gamma spectrum measurement route is expanded to 800m on the basis of the grid line spacing of the conventional gamma spectrum measurement route; the adjustment range of the grid line spacing of the gamma spectrum measurement route shall not exceed 1 / 2 of the grid line spacing of the conventional gamma spectrum measurement route.

[0043] When designing a gamma spectrum measurement route for a certain area, if some important known radioactive anomaly information is encountered and the conventional gamma spectrum measurement route cannot take it into account or the extension range of the radioactive anomaly points of two adjacent conventional gamma spectrum measurement routes is suddenly reduced, an unconventional gamma spectrum measurement short line is added on the basis of the conventional gamma spectrum measurement route.

[0044] For example, radioactive anomaly points 7-104 and 85-3 are both relatively important mineralized anomalies in the trachyte silicification zone. Since the conventional gamma spectrum measurement route cannot take both into account at the same time, an unconventional gamma spectrum measurement short line is added near radioactive anomaly point 85-3, which runs through radioactive anomaly points 7-104 and 85-3. In the subsequent measurement process of the actual gamma spectrum measurement route, a new radioactive anomaly point 85-7 was discovered on this unconventional gamma spectrum measurement short line. In addition, during the actual measurement of the gamma energy spectrum measurement route, the extension range of the radioactive anomaly points of the two adjacent conventional gamma energy spectrum measurement routes was suddenly reduced, and a short line control was added. Hundreds of meters of radioactive anomalies were found in the conventional gamma energy spectrum measurement route adjacent to the radioactive anomaly points 4-7, while the radioactive anomalies of the adjacent conventional gamma energy spectrum measurement routes disappeared directly. It is speculated that the grid line spacing of the gamma energy spectrum measurement route in this section cannot be effectively controlled, affecting the accuracy of the radioactive anomaly range delineation. Therefore, an unconventional gamma energy spectrum measurement short line was added between the two conventional gamma energy spectrum measurement routes. The length of the unconventional gamma energy spectrum measurement short line was based on the anomaly extension length of the conventional gamma energy spectrum measurement route with the larger anomaly in the two conventional gamma energy spectrum measurement routes, and the two ends were appropriately lengthened.

[0045] A small number of sections were fine-tuned based on actual conditions, and the rest were carried out according to the conventional gamma spectroscopy measurement route network.

[0046] Table 3 Score table of elements extracted by multivariate information fusion in each section of a certain region

[0047]

[0048]

[0049]

[0050]

[0051]

[0052] Step 3: According to the gamma spectrum measurement route designed in step 2, the ground gamma spectrum measurement route is measured in a certain area in accordance with the requirements of the ground gamma spectrum measurement specification; during the measurement of the gamma spectrum measurement route, when the gamma spectrum measurement route deviates from the radioactive anomaly point within 100m, the gamma spectrum measurement route is measured near the radioactive anomaly point within the gamma spectrum measurement route deviation range required by the ground gamma spectrum measurement specification; when the gamma spectrum measurement route deviates from the important radioactive anomaly point by more than 100m, refer to step 2 to add an encrypted gamma spectrum measurement short line to measure the gamma spectrum measurement route; the gamma spectrometer measurement data is continuously turned on during the travel between measurement points. If it is found that the data between measurement points is abnormally increased, the encrypted fixed-point gamma spectrum measurement is performed, and the encrypted point distance is controlled at 50m or 20m according to the radioactive anomaly range and radioactivity intensity.

[0053] During the measurement of the gamma spectrum measurement route, affected by the grid density of the gamma spectrum measurement route, part of the gamma spectrum measurement route deviates from the radioactive anomaly point. When the gamma spectrum measurement route deviates from the radioactive anomaly point within 100m, the gamma spectrum measurement route is measured close to the radioactive anomaly point within the gamma spectrum measurement route deviation range required by the ground gamma spectrum measurement specification.

[0054] For example, a new radioactive anomaly point 85-6 is discovered on the gamma spectrum measurement route that passes through the radioactive anomaly point 7-104, but the extension direction of the radioactive anomaly point 85-6 is northwest. In order to control the extension range of the radioactive anomaly point 85-6, the gamma spectrum measurement route is measured along the northwest direction close to the radioactive anomaly point 85-6 within the gamma spectrum measurement route deviation range required by the ground gamma spectrum measurement specification, and then gradually approaches the gamma spectrum measurement route designed in step 2.

[0055] During the measurement of the gamma spectrum measurement route, when the gamma spectrum measurement route deviates from the important radioactive anomaly point by more than 100m, refer to step 2 to add an encrypted gamma spectrum measurement route. For example, when the gamma spectrum measurement route deviates from the important radioactive anomaly point 85-3 by more than 100m, add an encrypted gamma spectrum measurement route near the important radioactive anomaly point 85-3.

[0056] In the measurement process of the existing gamma spectrum measurement route, the process of traveling between measurement points is to carry the gamma spectrometer to the measurement point to start measurement, and there is a measurement blank between measurement points. In the measurement process of the gamma spectrum measurement route of the present invention, the gamma spectrometer is continuously turned on to measure data during the process of traveling between measurement points. The stability of the data continuously measured during the process of traveling between measurement points is relatively poor, and only monitoring is performed without saving. If it is found that the data continuously measured during the process of traveling between measurement points is abnormally increased, an encrypted fixed-point gamma spectrum measurement is performed. For example, the radioactive abnormal point 85-6 is a newly discovered radioactive abnormal point monitored by the data continuously measured during the process of traveling between measurement points.

[0057] The measurement at the measuring point must be completed stably at the measuring point, at least one set of stable data must be measured at each measuring point, and each measurement time is 1 minute as required by the gamma spectrometer specification. This method is used to avoid the omission of small-scale anomalies between point distances as much as possible.

[0058] Step 4: Conduct on-site verification of known radioactive anomaly information not found in step 3 to fill in the gaps; then, conduct preliminary processing of the measurement data of the gamma spectrum measurement route in step 3 to understand the intensity and distribution of radioactive anomalies found during the measurement of the ground gamma spectrum measurement route, and then compare and study the important radioactive anomaly information identified and screened out in step 1 to screen out radioactive anomalies with considerable radioactive intensity or distribution scale, and at the same time mark the important radioactive anomalies and geophysical and chemical anomalies that were not found during the measurement of the gamma spectrum measurement route, and add encrypted gamma spectrum measurement short lines to measure the gamma spectrum measurement route to avoid missing key radioactive anomalies.

[0059] During the measurement work of the gamma-ray spectrum measurement route in a certain area, the radioactive anomaly points 4-6 and 4-8 mentioned in previous data, as well as the uranium anomaly halos in the north of section G and section H were not measured as anomalies. We conducted a check and fill in the gaps for these relatively typical and large-scale anomaly information.

[0060] After detailed field measurements and verifications, it was found that the radioactive anomaly points 4-6 and the uranium anomaly halo in section H had been destroyed due to the construction of reservoirs and roads, no anomalies were found in the artificial outcrops of the mountain, and no obvious anomalies were found in the northern uranium anomaly halo in section G during the field verification. The final result shall be based on actual measurements. After verification, obvious anomalies were found near the survey line at radioactive anomaly point 4-8, and of a certain scale. Supplementary and encrypted short-line control was then carried out to avoid the omission of key radioactive anomalies.

[0061] Step 5: Comprehensively analyze the gamma spectrum measurement data of steps 3 and 4 and the gamma spectrum measurement verification results of step 4, and further screen out radioactive anomaly points 4-7, 7-8, 7-104, 85-3, 85-6, 85-7 and 85-8 with considerable radioactive intensity or distribution scale. Carry out detailed field repeated inspection and measurement and mineralization point inspection for these radioactive anomaly points, record their mineralization scale, mineralization type, alteration type, occurrence lithology and surrounding rock characteristics in detail, and make preliminary evaluation to screen out important radioactive anomaly point belts; for some radioactive anomaly points with small scale but good prospects, they are appropriately magnified in the process of delineating the anomaly halo. For example, the 85-3 uranium ore point, although the mineralization scale is not large, the radioactive intensity is high, the ore-controlling factors are obvious, the ore-controlling structure extends on a large scale, and the prospect is good. It is appropriately magnified in the subsequent comprehensive delineation of the anomaly halo.

[0062] Step 6: Process and analyze the gamma spectrum measurement data of steps 3, 4 and 5 in detail, draw plane profiles and contour maps of uranium, thorium, potassium and total amount, and then, based on the distribution characteristics of uranium, thorium, potassium and total amount and the inspection results of step 5, circle out the abnormal areas where the content of uranium, thorium and potassium is greater than or equal to 3 times the background average value of the geological body; circle out the abnormal areas whose abnormal range is controlled by the same layer or structure, extend more than 20m or have a total length of more than 40m intermittently as abnormal halos, among which the abnormalities near sections D and E are controlled by perlite in the same layer and extend on a large scale, and 3 abnormal halos are circled; the abnormal area near section C is obviously controlled by the structure and the surface abnormality intensity is high, so it is appropriately magnified and 2 abnormal halos are circled, and a total of 5 abnormal halos are circled.

[0063] A comprehensive analysis was conducted on the attributes of the anomaly halos, such as the size of the anomaly, the strength of the anomaly, the clarity of the controlling factors, the correlation of the anomaly types and the consistency of the multivariate information. A comprehensive ranking was conducted based on the favorableness of the attributes. All five anomaly halos were target types with clear controlling factors. Among them, the anomaly halo in the west of section C had high anomaly intensity, obvious structural control, large scale, and good consistency between the ore points and the ground radioactive anomalies, ranking first; the anomaly halos in sections E and D had large scale, high anomaly intensity, obvious control by perlite strata, and good consistency with the multivariate information, ranking second and third respectively; the anomaly halos in the east of section C and the north of section D had relatively small scale, high anomaly intensity, obvious control by perlite strata, and good consistency with the multivariate information, ranking fourth and fifth respectively.

[0064] Finally, a comprehensive prospect prediction is made on the basis of the sorting of anomaly halos, and a comprehensive classification is made by combining geological bodies, structures, existing radioactive data, the degree of agreement between multivariate information and anomaly halos, and other attributes of anomaly halos. The two anomaly halos in the east and west of section C are close to each other, and the three anomaly halos in sections E and D are controlled by the northeast-trending fissure volcanic structure, so they are merged and two uranium mineralization prospective areas in sections C and D are predicted in a certain area. Among them, the section near section C with good anomaly display, favorable mineralization conditions, high degree of agreement with multivariate information, 85-3 mineral point has been discovered, and good prospecting prospect is predicted as a Class II prospective area; the section around section D with good anomaly display, favorable mineralization conditions, good degree of agreement with multivariate information, unclear mineralization, and unclear prospecting prospect is predicted as a Class III prospective area.

[0065] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for delineating abnormal halos in ground gamma spectrum area measurement work, characterized in that: The steps include: Step 1: Conduct comprehensive analysis and research based on the existing radioactive data in the work area, extract the existing radioactive anomaly information in the work area, identify and screen out the important radioactive anomaly information in the work area, and conduct field surveys in the sections of the work area where there is important radioactive anomaly information; Step 2: Based on the comprehensive analysis and research and exploration of step 1, combined with the work stage, work area and geological complexity, and in accordance with the requirements of ground gamma spectrum measurement specifications, select the gamma spectrum measurement route network; conduct a comprehensive score ranking of each section of the work area, and design a gamma spectrum measurement route based on the conventional gamma spectrum measurement route according to the comprehensive score ranking results of each section of the work area; Step 3: According to the gamma spectrum measurement route designed in step 2, the gamma spectrum measurement route is measured in the work area in accordance with the ground gamma spectrum measurement specification requirements. During the measurement of the gamma spectrum measurement route, the gamma spectrometer measurement data is continuously turned on; Step 4: Conduct on-site verification of the important radioactive anomaly information screened out in step 1 and the known radioactive anomaly information not found in step 3. If radioactive anomalies are confirmed, the gamma spectrum measurement short line is promptly supplemented to conduct gamma spectrum measurement route measurement to complete the missing check; Step 5: Comprehensively analyze the gamma spectrum measurement data of steps 3 and 4 and the gamma spectrum measurement verification results of step 4, further screen out radioactive anomalies with considerable radioactive intensity or distribution scale, and conduct repeated field inspections and mineralization point inspections; Step 6: Based on the gamma spectrum measurement data of steps 3, 4 and 5, draw a plane section view and a series of contour maps, and then circle out the abnormal halos in combination with the inspection results of step 5; Comprehensively sort the abnormal halos and make comprehensive prospect predictions in combination with other geological information; In step 3, during the measurement of the gamma spectrum measurement route, when the gamma spectrum measurement route deviates from the radioactive anomaly point within 100m, the gamma spectrum measurement route is measured near the radioactive anomaly point within the gamma spectrum measurement route deviation range required by the ground gamma spectrum measurement specification; when the gamma spectrum measurement route deviates from the important radioactive anomaly point by more than 100m, refer to step 2 to add an encrypted gamma spectrum measurement short line to measure the gamma spectrum measurement route; the gamma spectrometer measurement data is continuously turned on during the travel between measurement points. If it is found that the data between the measurement points is abnormally increased, an encrypted fixed-point gamma spectrum measurement is performed, and the encrypted point distance is controlled at 50m or 20m according to the radioactive anomaly range and the radioactivity intensity; at least one set of stable data is measured at each measurement point, and the measurement time for each measurement is the time required by the gamma spectrometer specification.

2. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 1, characterized in that: In step 1, the existing radioactive results data include existing uranium exploration data, aerial radioactive work data, ground radioactive work data, surface radioactive anomaly point belt information and geophysical and geochemical exploration results data; the existing radioactive anomaly information includes existing radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration anomaly information.

3. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 1, characterized in that: In step 2, the elements of the multivariate information of each section of the working area are fused and extracted, and the fused and extracted elements of each section of the working area are scored. The arithmetic sum of the scores of the fused and extracted elements of each section of the working area is the comprehensive score of each section of the working area. The comprehensive scores of each section of the working area are ranked, and the gamma energy spectrum measurement route is designed based on the conventional gamma energy spectrum measurement route according to the ranking results of the comprehensive scores of each section of the working area.

4. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 3, characterized in that: The multivariate information includes known radioactive anomaly information and exploration status information, and the known radioactive anomaly information includes known radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration radioactive anomaly information. The following elements are extracted from the known radioactive anomaly point belt information, ground radioactive anomaly information, aerial radioactive anomaly information and geophysical and geochemical exploration radioactive anomaly information: radioactive intensity, distribution scale, mineralization type and distribution morphology; the following elements are extracted from the exploration status information: work degree, work stage, work method and exploration results, and each section of the work area is comprehensively scored according to the following table:

5. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 4, characterized in that: In step 2, the design of the gamma spectrum measurement route should take into account the known radioactive anomaly information and highlight the key points. For sections with a comprehensive score higher than 30 points, the grid line spacing of the gamma spectrum measurement route should be reduced on the basis of the grid line spacing of the conventional gamma spectrum measurement route. For sections with a comprehensive score lower than 10 points, the grid line spacing of the gamma spectrum measurement route should be expanded on the basis of the grid line spacing of the conventional gamma spectrum measurement route. The adjustment range of the gamma spectrum measurement route grid line spacing shall not exceed 1 / 2 of the grid line spacing of the conventional gamma spectrum measurement route. If some important radioactive anomaly information is encountered and the conventional gamma spectrum measurement route cannot be taken into account or the extension range of the radioactive anomaly of two adjacent gamma spectrum measurement routes is suddenly reduced, an unconventional gamma spectrum measurement short line shall be added.

6. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 1, characterized in that: In step 4, the known radioactive anomaly information not found in step 3 is verified on the spot to find out the omissions and fill the gaps; then, the measurement data of the gamma energy spectrum measurement route in step 3 is preliminarily processed to understand the intensity and distribution of the radioactive anomalies found in the measurement process of the ground gamma energy spectrum measurement route, and then compared with the important radioactive anomaly information identified and screened out in step 1, and the radioactive anomalies with relatively considerable radioactive intensity or distribution scale are screened out. At the same time, the important radioactive anomalies and geophysical and chemical anomalies that were not found in the measurement process of the gamma energy spectrum measurement route are marked, and an encrypted gamma energy spectrum measurement short line is added to measure the gamma energy spectrum measurement route.

7. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 1, characterized in that: In step 5, during the repeated on-site inspection and measurement of radioactive anomalies and the inspection of mineralized points, the scale of mineralization, type of mineralization, type of alteration, lithology and surrounding rock characteristics are recorded in detail, and a preliminary evaluation is conducted to screen out important radioactive anomaly points and belts; for some small-scale but promising radioactive anomalies, they are magnified during the process of anomaly halo identification.

8. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 1, characterized in that: In step 6, the gamma spectrum measurement data of steps 3, 4 and 5 are processed and analyzed in detail, and the plane profile and the contour map of uranium, thorium, potassium and total amount are drawn. Then, in combination with the distribution characteristics of uranium, thorium, potassium and total amount and the inspection results of step 5, the abnormal area with uranium, thorium and potassium content greater than or equal to 3 times the background average value of the geological body is circled; the abnormal area whose abnormal range is controlled by the same layer or structure, extends more than 20m or has a total length of more than 40m is circled as abnormal halo; the attributes of the abnormal halo are comprehensively analyzed, and the attributes of the abnormal halo are comprehensively ranked according to their favorableness; on the basis of the comprehensive ranking of the abnormal halo, a comprehensive prospect prediction is carried out, and the geological body, structure, existing radioactive results data, the degree of coincidence of multivariate information with the abnormal halo and other attributes of the abnormal halo are comprehensively graded, and the section with good abnormal display, very favorable mineralization conditions, high degree of coincidence of multivariate information, discovered mineral points or industrial mineralization, and good prospecting prospect is predicted as Class I prospective area; The sections with good anomaly display, favorable mineralization conditions, high degree of consistency of multivariate information, discovered mineral points or mineralization, and good prospecting prospects are predicted as Class II prospecting areas; The sections with good anomaly display, favorable mineralization conditions, average consistency of multivariate information, unclear mineralization and unclear prospecting prospects are predicted to be Class III prospective areas.

9. The method for delineating abnormal halos in ground gamma spectrum area measurement work according to claim 8, characterized in that: The attributes of the anomaly halo include size, anomaly strength, degree of clarity of control factors, degree of correlation of anomaly types and degree of consistency of multivariate information.

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