Deeply buried gravel pore brine potash mine exploration and evaluation method

Abstract

The application discloses a kind of deeply buried gravel pore brine potassium ore exploration evaluation method, comprising: by regional remote sensing interpretation, regional gravity measurement, three kinds of methods such as small-scale regional geological survey effectively delineate piedmont alluvial-proluvial zone, preliminary determine gravel pore brine potassium ore deposit prospecting target area, in the delineated prospecting target area, by carrying out seismic survey and selectively implementing wide area electromagnetic measurement, oil well investigation, preparing lithofacies paleogeographic map and the like, effectively determine the distribution range and horizon of gravel pore brine. Further, by implementing drilling engineering, comprehensive logging, comprehensive well logging, core logging, pumping test, sample analysis test, accurately delineate gravel pore brine potassium ore deposit, and according to brine deposit distribution area, brine layer thickness, useful component content, porosity, water supply degree and the like parameter calculation resource reserves, realize the purpose of evaluating deposit.

Description

Technical Field

[0001] This invention belongs to the field of salt lake resource exploration technology, and in particular relates to a method for exploring and evaluating potassium deposits in deep-buried gravel pore brine. Background Technology

[0002] Potash fertilizer is one of the three major agricultural fertilizers. Currently, my country's potash fertilizer self-sufficiency rate is still significantly insufficient, and there is an urgent need to expand production capacity and improve supply security. Deep brine resources have enormous potential and are the only alternative resource. Therefore, it is necessary to increase potash fertilizer security capacity and establish new potash fertilizer production bases. Gravelly porous brine potash deposits are also attracting increasing attention. Deeply buried gravelly porous brine potash deposits, being a new type of brine potash deposit, have rarely been specifically explored and evaluated in the past. In recent years, evaluation work on gravelly porous brine potash deposits has been carried out successively, thus requiring a systematic and complete evaluation method for gravelly porous brine potash deposits to guide exploration work. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention proposes a method for exploring and evaluating potash deposits in deep-buried gravel and porous brine, thereby resolving the issues present in the existing technologies.

[0004] To achieve the above objectives, the present invention provides a method for exploring and evaluating potash deposits in deep-buried gravel porous brine, comprising:

[0005] Analyze the alluvial fan area in front of the mountain in the area to be explored to determine the initial distribution range of gravel porous brine potassium deposits as the prospecting target area;

[0006] The distribution range and stratigraphic position of sand and gravel pore brine in the prospecting target area were obtained based on seismic measurement data analysis.

[0007] Based on the distribution range and stratigraphic position of brine in gravel pores, field exploration was conducted to obtain effective parameters of the ore deposit.

[0008] Based on the effective parameters of the deposit, a target area is selected, and the deposit resource reserves are calculated to obtain an exploration report for deep-buried gravel porous brine potassium deposit, thus completing the exploration and evaluation.

[0009] Optionally, the process of determining the initial distribution range of gravel porous brine potash deposits includes: using regional remote sensing interpretation, regional gravity measurement, and small-to-medium scale regional geological survey to verify the area to be explored, obtaining the first block, the second block, and the third block of the piedmont alluvial-diluvial zone, and taking the union of the first block, the second block, and the third block as the initial distribution range.

[0010] Optionally, the process of obtaining the distribution range and stratigraphic position of gravel pore brine in the prospecting target area includes: interpreting seismic measurement data, determining the distribution range of gravel pore structures in the prospecting target area based on the interpretation results; selecting at least one method, such as wide-area electromagnetic survey, oil well survey, or compiling lithofacies paleogeographic maps, to verify the distribution range and determine the distribution range and stratigraphic position of gravel pore brine in the prospecting target area.

[0011] Optionally, determine whether the seismic data interpretation results for the corresponding area include chaotic reflection phases, relatively continuous wedge-shaped reflection phases with strong and weak amplitudes at medium frequencies, subparallel discontinuous phases with medium amplitudes at medium frequencies, relatively continuous wave-like phases with medium and weak amplitudes at high frequencies, and relatively continuous subparallel phases with medium and weak amplitudes at medium and high frequencies. Based on the determination results, confirm whether there are sand and gravel pore structures.

[0012] Optionally, the process of obtaining effective parameters of a mineral deposit includes:

[0013] Underground core samples are obtained through drilling. Based on the underground core samples, the effective parameters of the deposit are determined by combining comprehensive well logging, core logging, pumping and drainage tests, and sample analysis and testing. The effective parameters of the deposit include, but are not limited to, deposit area, thickness, porosity, water yield, content of useful components, and specific gravity.

[0014] Optionally, the process of obtaining underground core samples includes:

[0015] Geological data is acquired and a three-dimensional geological model is constructed. Based on the three-dimensional geological model, the accurate location, shape, size and continuity of the ore body are identified. Based on the three-dimensional geological model, the distribution range of sand and gravel pore brine and the stratigraphic position, drilling targets are selected. Drilling engineering parameters are determined according to the accurate location, shape, size and continuity of the ore body. The drilling engineering parameters include borehole spacing, borehole depth, borehole diameter and borehole direction.

[0016] Optionally, the drilling diameter includes 450mm, 377mm, 273mm, 168mm, 127mm, and 108mm.

[0017] Optionally, the process of calculating the mineral deposit resource reserves includes: setting a preset parameter threshold, selecting a target area based on the effective parameters and the parameter threshold, using the block estimation method to spatially interpolate the content of useful components in the ore body, calculating the ore body volume and determining the ore body density through sampling, and calculating the mineral deposit resource reserves based on the ore body volume, the ore body density, and the content of useful components.

[0018] Compared with the prior art, the present invention has the following advantages and technical effects:

[0019] This invention effectively delineates piedmont alluvial-diluvial zones and preliminarily identifies prospecting target areas for gravelly porous brine potash deposits through three methods: regional remote sensing interpretation, regional gravity measurement, and small-to-medium scale regional geological surveying. Based on this, within the delineated prospecting target areas, seismic surveys, selective wide-area electromagnetic surveys, oil well investigations, and the compilation of lithofacies paleogeographic maps can effectively determine the distribution range and stratigraphic position of gravelly porous brine. Furthermore, through drilling, integrated logging, comprehensive well logging, core logging, pumping tests, and sample analysis, gravelly porous brine potash deposits can be accurately delineated. Resource reserves can be calculated based on parameters such as brine deposit distribution area, brine layer thickness, useful component content, porosity, and specific yield, thus achieving the purpose of deposit evaluation. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0021] Figure 1 This is a schematic diagram of the method flow according to an embodiment of the present invention. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0024] Example 1

[0025] like Figure 1 As shown in this embodiment, a method for exploring and evaluating potash deposits in deep-buried gravel porous brine is provided, including:

[0026] The process involves delineating the alluvial-diluvial zone at the foot of the mountain and identifying the target area; determining the distribution range and stratigraphic position of brine in the sand and gravel pores; delineating the ore body, calculating resource reserves, and evaluating the deposit.

[0027] In some embodiments, the alluvial fan area in front of the mountain in the area to be explored is analyzed to determine the initial distribution range of gravel porous brine potassium deposits as prospecting target areas;

[0028] The distribution range and stratigraphic position of sand and gravel pore brine in the prospecting target area were obtained based on seismic measurement data analysis.

[0029] Based on the distribution range and stratigraphic position of brine in gravel pores, field exploration was conducted to obtain effective parameters of the ore deposit.

[0030] Based on the effective parameters of the deposit, a target area is selected, and the deposit resource reserves are calculated to obtain an exploration report for deep-buried gravel porous brine potassium deposit, thus completing the exploration and evaluation.

[0031] Specifically, the delineation of the piedmont alluvial-diluvial zone and the determination of the target area are determined by a combination of three methods: regional remote sensing interpretation, regional gravity measurement, and small-to-medium scale regional geological surveying; the determination of the distribution range and stratigraphic position of sand and gravel pore brine is determined by a combination of four methods: seismic surveying, wide-area electromagnetic surveying, oil well surveying, and compilation of lithofacies paleogeographic maps; and the delineation of ore bodies, calculation of resource reserves, and evaluation of ore deposits are determined by a combination of six methods: drilling engineering, integrated logging, integrated well logging, core logging, pumping tests, and sample analysis and testing.

[0032] In some preferred embodiments, the process of determining the initial distribution range of gravel porous brine potash deposits includes: using regional remote sensing interpretation, regional gravity measurement, and small-to-medium scale regional geological survey to authenticate the area to be explored, obtaining the first block, the second block, and the third block of the piedmont alluvial-diluvial zone, and taking the union of the first block, the second block, and the third block as the initial distribution range.

[0033] Specifically, the target area should meet at least one of the following conditions: the regional remote sensing interpretation results identify the target body as a piedmont alluvial-diluvial zone; the comprehensive analysis results of regional gravity measurement data identify the target body as a piedmont alluvial-diluvial zone; or the results of small-to-medium scale regional geological surveys identify the target body as a piedmont alluvial-diluvial zone.

[0034] In some specific embodiments, the process of obtaining the distribution range and stratigraphic position of gravel pore brine in the prospecting target area includes: interpreting seismic measurement data, determining the distribution range of gravel pore structures in the prospecting target area based on the interpretation results; selecting at least one method, such as wide-area electromagnetic survey, oil well survey, or compiling lithofacies paleogeographic maps, to verify the distribution range and determine the distribution range and stratigraphic position of gravel pore brine in the prospecting target area.

[0035] Specifically, determining the distribution range and stratigraphic position of gravelly porous brine should at least meet one of the following conditions: seismic data interpretation results confirm the presence of gravelly porous strata capable of storing brine within the prospecting target area of ​​the alluvial-diluvial region identified in the first stage; wide-area electromagnetic survey results infer or confirm the existence of brine reservoirs within the prospecting target area of ​​the alluvial-diluvial region identified in the first stage; oil well survey results show that brine storage space or brine containing useful components has been found in previous drillings within the prospecting target area of ​​the alluvial-diluvial region identified in the first stage; and the results of compiling lithofacies paleogeographic maps show that there is a sedimentary environment with gravelly porous brine potassium deposits within the prospecting target area of ​​the alluvial-diluvial region identified in the first stage.

[0036] Specifically, the interpretation results of the seismic survey data identify sand-gravel porous structures capable of storing brine, which generally possess the following characteristics: chaotic reflections correspond to alluvial fan reservoirs; relatively continuous wedge-shaped reflections with strong and weak amplitudes and mid-frequency characteristics correspond to fan delta reservoirs, which are important reservoirs for finding sand-gravel porous brine potash deposits. Medium-amplitude, mid-frequency, subparallel, discontinuous reflections correspond to chemical sedimentary layers, reflecting salt deposition in this layer, which are also important reservoirs for finding sand-gravel porous brine potash deposits. Medium-weak amplitude, high-frequency, medium-to-relatively continuous wavy reflections correspond to littoral-shallow lacustrine facies reservoirs; medium-weak amplitude, mid-to-high-frequency, relatively continuous, subparallel reflections correspond to shallow lacustrine facies reservoirs, which are common reservoirs for sand-gravel porous brine potash deposits.

[0037] To delineate ore bodies, calculate resource reserves, and evaluate deposits, drilling, integrated logging, pumping tests, and sample testing must be conducted to obtain resource reserve calculation parameters for gravelly porous brine potash deposits. The evaluation of gravelly porous brine potash deposits can be achieved when the drilling quality meets the requirements for integrated logging, pumping tests, and sample analysis; when the integrated logging data interpretation shows an aquifer meeting the evaluation criteria; when the pumping test results indicate the existence of a water-rich reservoir; and when the sample testing results show that the useful components in the brine meet the evaluation indicators.

[0038] In some specific embodiments, the process of obtaining effective parameters of the ore deposit includes:

[0039] Underground core samples are obtained through drilling. Based on the underground core samples, the effective parameters of the deposit are determined by combining comprehensive well logging, core logging, pumping and drainage tests, and sample analysis and testing. The effective parameters of the deposit include, but are not limited to, deposit area, thickness, porosity, water yield, content of useful components, and specific gravity.

[0040] The process of obtaining underground rock core samples includes:

[0041] Geological data is acquired and a three-dimensional geological model is constructed. Based on the three-dimensional geological model, the accurate location, shape, size and continuity of the ore body are identified. Based on the three-dimensional geological model, the distribution range of sand and gravel pore brine and the stratigraphic position, drilling targets are selected. Drilling engineering parameters are determined according to the accurate location, shape, size and continuity of the ore body. The drilling engineering parameters include borehole spacing, borehole depth, borehole diameter and borehole direction.

[0042] In some preferred embodiments, the process of calculating the mineral deposit resource reserves includes: setting a preset parameter threshold, selecting a target area based on the effective parameters and the parameter threshold, using the block estimation method to spatially interpolate the useful component content of the ore body, calculating the ore body volume and determining the ore body density by sampling, and calculating the mineral deposit resource reserves based on the ore body volume, the ore body density, and the useful component content.

[0043] Specifically, in addition to drilling, integrated logging, pumping tests, and sample testing, integrated logging and core logging can be selectively carried out to help identify water-bearing strata.

[0044] Specifically, the drilling project is carried out with different diameters depending on the differences in the target body and the needs of the exploration work, including but not limited to 450mm, 377mm, 273mm, 168mm, 127mm and 108mm.

[0045] Specifically, the comprehensive logging includes, but is not limited to, the following: cuttings logging, wellbore coring, drilling time, gas logging, drilling parameters, drilling fluid parameters, and electrical conductivity parameters. Among these, cuttings logging, wellbore coring, and drilling time parameters primarily reflect formation lithological characteristics; gas logging, drilling parameters, drilling fluid parameters, and electrical conductivity parameters comprehensively reflect the characteristics of brine-bearing layers. Combining these two methods allows for a comprehensive determination of the stratigraphic distribution of gravelly porous brine potash deposits.

[0046] Specifically, the integrated logging includes, but is not limited to, the following: compensated neutron, compensated density, array acoustic logging, wellbore diameter, natural gamma ray, gamma spectrum, spontaneous potential, apparent resistivity, and array induction. Among these, compensated neutron, compensated density, array acoustic logging, wellbore diameter, natural gamma ray, gamma spectrum, and spontaneous potential primarily identify gravelly porous brine potash reservoirs; apparent resistivity and array induction primarily identify the presence of gravelly porous brine potash deposits. The combination of these two methods can accurately determine the distribution location of gravelly porous brine potash deposits.

[0047] Specifically, the sample testing includes the following: K+, Na+, Ca2+, Mg2+, Li+, B2O3, Cl-, SO42-, HCO3-, CO32-, Rb+, Cs+, Sr2+, Br-, I-, NO3-, Fe3+, Ba2+, Cu2+, Pb2+, Zn2+, As-, F-, pH value, density, mineralization, porosity, water supply, and permeability.

[0048] Specifically, the sample tests, including pH value, density, mineralization, porosity, water yield, and permeability, are important parameters for calculating resource quantity. Useful components such as K+, Na+, Ca2+, Mg2+, Li+, B2O3, Cl-, SO42-, HCO3-, CO32-, Rb+, Cs+, Sr2+, Br-, I-, NO3-, Fe3+, Ba2+, Cu2+, Pb2+, Zn2+, As-, and F- can be increased or decreased according to actual conditions.

[0049] This embodiment comprehensively determines the possible distribution range of gravelly porous brine potash deposits through lithofacies paleogeography, regional remote sensing interpretation, regional gravity measurement, and field reconnaissance methods. It preliminarily determines the possible distribution range of gravelly porous brine potash deposits and identifies prospecting target areas, thus completing the first phase of work. Within the possible distribution range of gravelly porous brine potash deposits delineated in the first phase, through seismic measurement and interpretation, combined with previous geological data, and other methods, a comprehensive study and detailed analysis are conducted to determine the horizontal and vertical distribution range and stratigraphic position of the gravelly porous brine potash deposits. Drilling operations are precisely deployed, and an exploration plan for deeply embedded gravelly porous brine potash deposits is prepared, completing the second phase of work. Based on the exploration plan determined in the second phase, field work is carried out. Using drilling operations, integrated well logging, core logging, pumping (draining) tests, and sample analysis and testing methods, parameters such as deposit area, thickness, porosity, water yield, useful component content, and specific gravity are comprehensively determined, completing the third phase. Based on the effective parameters obtained in the third phase, the target area for rich ore was delineated, the mineral resource reserves were calculated, an exploration report on deep-buried gravel porous brine potassium ore was prepared, and the mineral deposit evaluation was completed.

[0050] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for exploring and evaluating potash deposits in deep-buried gravel and porous brine, characterized in that, Includes the following steps: Analyze the alluvial-diluvial zone in front of the mountain in the area to be explored to determine the initial distribution range of gravel porous brine potassium deposits, which can be used as prospecting target areas; The distribution range and stratigraphic position of sand and gravel pore brine in the prospecting target area were obtained based on seismic measurement data analysis. Based on the distribution range and stratigraphic position of brine in gravel pores, field exploration was conducted to obtain effective parameters of the ore deposit. Based on the effective parameters of the deposit, the target area is selected, the deposit resource reserves are calculated, an exploration report of deep-buried gravel porous brine potassium deposit is obtained, and the exploration evaluation is completed.

2. The method for exploring and evaluating deep-buried gravel-porous brine potassium deposits according to claim 1, characterized in that, The process of determining the initial distribution range of gravelly porous brine potash deposits includes: using regional remote sensing interpretation, regional gravity measurement, and small-to-medium scale regional geological surveys to verify the area to be explored, obtaining the first block, the second block, and the third block of the piedmont alluvial-diluvial zone, and taking the union of the first block, the second block, and the third block as the initial distribution range.

3. The method for exploring and evaluating deep-buried gravel-porous brine potassium deposits according to claim 1, characterized in that, The process of obtaining the distribution range and stratigraphic position of sand and gravel pore brine in the prospecting target area includes: interpreting seismic measurement data, determining the distribution range of sand and gravel pore structures in the prospecting target area based on the interpretation results; selecting at least one method, such as wide-area electromagnetic survey, oil well survey, or compiling lithofacies paleogeographic maps, to verify the distribution range and determine the distribution range and stratigraphic position of sand and gravel pore brine in the prospecting target area.

4. The method for exploring and evaluating deep-buried gravel-porous brine potassium deposits according to claim 3, characterized in that, Determine whether the seismic data interpretation results for the corresponding area include chaotic reflection phases, relatively continuous wedge-shaped reflection phases with strong and weak amplitudes at medium frequencies, subparallel discontinuous phases with medium amplitudes at medium frequencies, relatively continuous wave-like phases with medium and weak amplitudes at high frequencies, and relatively continuous subparallel phases with medium and weak amplitudes at medium and strong frequencies. Based on the determination results, confirm whether there are sand and gravel pore structures.

5. The method for exploring and evaluating deep-buried gravel-porous brine potassium deposits according to claim 1, characterized in that, The process of obtaining effective parameters of a mineral deposit includes: Underground core samples are obtained through drilling. Based on the underground core samples, the effective parameters of the deposit are determined by combining comprehensive well logging, core logging, pumping and drainage tests, and sample analysis and testing. The effective parameters of the deposit include, but are not limited to, deposit area, thickness, porosity, water yield, content of useful components, and specific gravity.

6. The method for exploring and evaluating deep-buried gravel-porous brine potassium deposits according to claim 5, characterized in that, The process of obtaining underground rock core samples includes: Geological data is acquired and a three-dimensional geological model is constructed. Based on the three-dimensional geological model, the accurate location, shape, size and continuity of the ore body are identified. Based on the three-dimensional geological model, the distribution range of sand and gravel pore brine and the stratigraphic position, drilling targets are selected. Drilling engineering parameters are determined according to the accurate location, shape, size and continuity of the ore body. The drilling engineering parameters include borehole spacing, borehole depth, borehole diameter and borehole direction.

7. The method for exploring and evaluating deep-buried gravel-porous brine potassium deposits according to claim 6, characterized in that, The borehole diameters include 450mm, 377mm, 273mm, 168mm, 127mm, and 108mm.

8. The method for exploring and evaluating deep-buried gravel-porous brine potassium deposits according to claim 1, characterized in that, The process of calculating mineral deposit reserves includes: setting a preset parameter threshold, selecting a target area based on the effective parameters and the parameter threshold, using the block estimation method to spatially interpolate the content of useful components in the ore body, calculating the ore body volume and determining the ore body density through sampling, and calculating the mineral deposit reserves based on the ore body volume, the ore body density, and the content of useful components.

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