A method for exploring hot water jet sedimentary cobalt ore

Abstract

The present invention discloses a method for prospecting hot water jet sedimentary cobalt ore, comprising the following steps: Step 1: compile a hot water sedimentary rock stratum distribution map, and preliminarily determine a favorable mineralization area; Step 2: compile a cobalt element anomaly map according to the results of the water system sediment measurement, and compile a target area comprehensive prediction map in combination with the stratum distribution map, and optimize the target area using the results of the water system sediment measurement; Step 3: carry out a special investigation, establish a marker layer, and then use the induced polarization profile and / or geochemical profile to conduct a preliminary verification of the target area and delineate the ore body; Step 4: use drilling for deep verification, and use borehole electrical logging to determine the deep ore layer, and use the comparison of lithology and rock layer thickness between different boreholes to comprehensively analyze the change law of the stratum and ore-bearing layer, and carry out a comprehensive evaluation of the cobalt ore in the area. The present invention has the characteristics of quickly identifying the cobalt-containing stratum, providing an implementation basis for trenching and drilling deployment, and can effectively improve the exploration efficiency and shorten the exploration cycle.

Description

Technical Field

[0001] The invention relates to the technical field of ore prospecting, and in particular to an exploration method for hot water jet sedimentation type cobalt ore. Background Art

[0002] Seafloor hydrothermal jet sedimentary deposits are one of the most important types of deposits in the world that produce metals such as copper, cobalt, lead, zinc, gold, silver and sulfur. Research on them not only has important theoretical significance, but also has important practical value in guiding mineral exploration.

[0003] The abundance of cobalt in the earth's crust is extremely low, and usually no independent cobalt deposits are formed. As a relatively dispersed element, cobalt can appear in a variety of sulfide deposits, and associated cobalt ore bodies can appear in cobalt-nickel deposits, copper ores, and iron ores. The cobalt currently being developed and utilized mainly comes from the associated components of copper, nickel, lead-zinc, and iron deposits. Cobalt-nickel deposits are mainly magmatic deposits, and hydrothermal jet sedimentary cobalt deposits are mostly associated minerals of copper, lead-zinc, and iron deposits. Due to the complexity of mineralization, the characteristics and signs of hydrothermal jet sedimentary cobalt deposits are still unclear, and the required technical methods are not the same. A single exploration method is also very limited in predicting this type of cobalt ore. If prospecting is carried out according to conventional exploration methods, it is possible to extend the exploration period, have low prospecting efficiency, and have unclear prospecting results. Summary of the invention

[0004] The present invention analyzes the seafloor jet-sedimentary mineralization characteristics and mineralization tectonic environment, and uses prediction theories such as "similar analogy", "geological anomaly", "ore deposit genetic model" or "ore-forming system" to roughly propose future prospecting directions and prospecting signs, with the aim of providing an exploration method for hot water jet-sedimentary cobalt deposits.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A method for exploring hot water jet sedimentary cobalt ore comprises the following steps:

[0007] Step 1: Hydrothermal jet deposition is often accompanied by the distribution of hydrothermal sedimentary rocks. Collect regional data to compile a hydrothermal sedimentary rock stratum distribution map and preliminarily determine the favorable mineralization area of ​​hydrothermal jet deposition type cobalt deposits;

[0008] Step 2: Cobalt is widely distributed on Earth, but its abundance in the crust is only 20×10 -6. Cobalt is iron-loving and sulfur-loving, and its geochemical behavior is very similar to that of iron and nickel. It is mostly produced as a co-occurring element in the deposits, and rarely forms cobalt deposits dominated by independent cobalt minerals. According to statistics, the hydrothermal jet sedimentary cobalt deposits in the East Kunlun metallogenic belt can be divided into copper-cobalt, iron-cobalt, and cobalt-gold combination types according to the material combination of cobalt. Based on the results of 1:500,000 or 1:200,000 stream sediment measurements, a cobalt element anomaly map is compiled, and combined with the hydrothermal sedimentary rock strata distribution map, a comprehensive prediction map of the target area is compiled. The results of 1:50,000 or 1:25,000 stream sediment measurements are used to further decompose the anomalies and optimize the target area;

[0009] Step 3: Exhalative sedimentary rock series are the products of exhalative basin sedimentation. The products of exhalative sedimentation are exhalative sedimentary rocks and sulfide layers. Various primary metal sulfide ores can cause low-resistance and high-polarization anomalies. Based on step 2, a special survey is carried out in the target area. A marker layer is established using a 1:10,000 special geological map. Then, the target area is preliminarily verified using induced polarization profiles and / or geochemical profiles to delineate the ore body.

[0010] Step 4: Based on step 3, deep verification is carried out by drilling, and deep mineral layers are determined by borehole electrical logging. The borehole logging data can be used to divide different stratigraphic interfaces in detail, discover and delineate mineral (chemical) layers. By comparing the lithology and rock layer thickness between different boreholes, a comprehensive analysis of the change patterns of the stratigraphic and mineral-bearing layers in the entire survey area is conducted, and a comprehensive evaluation of the cobalt mines in the area is carried out to determine in detail the number, shape, scale, occurrence and grade changes of surface ore bodies and mineralized bodies.

[0011] Preferably, step one collects a regional 1:50,000 geological and mineral map and / or a 1:250,000 geological and mineral map, and if necessary, prepares a hydrothermal sedimentary rock stratum distribution map in combination with a field route geological survey.

[0012] Preferably, the cobalt element anomaly map in step 2 includes a cobalt-gold element combination anomaly map, a cobalt-iron-lead-zinc element combination anomaly map, and a cobalt-copper element combination anomaly map.

[0013] Preferably, in step three, the induced polarization anomaly area with low resistance and high polarization characteristics is used to delineate the ore body in the induced polarization profile results; the section where the Co element in the geochemical profile is higher than the background value of the entire profile is used as the abnormal section to delineate the ore body; the scale of the induced polarization profile and / or geochemical profile is 1:2000 or 1:5000.

[0014] Preferably, in step three, the ore body is delineated based on the apparent polarizability of 6.97-17.24% in the induced polarization profile results.

[0015] Preferably, in step 4, chemical samples are taken in the drilling project to analyze the Co element value, and the ore body is defined as having a cut-off grade greater than 0.02%.

[0016] Preferably, in step 4, the natural potential curve obtained by borehole logging has no obvious difference in various rock and mineral layers, and there is an obvious low-resistance and high-polarization anomaly in the known mineralized (mineralized) layer to verify the ore body.

[0017] The beneficial effects of the present invention are as follows:

[0018] The present invention discloses a prediction and exploration method for hot water jet sedimentary cobalt ore in orogenic belts. Cobalt is mostly produced as associated metals in nature, and rarely forms independent or cobalt-based industrial deposits. The cobalt currently used in industry is mainly a byproduct recovered when processing copper, nickel, iron and other minerals. The present invention uses cobalt as the main mineral species to carry out prediction and exploration, identifies hot water sedimentary rocks, uses geophysical and geochemical exploration and other means to delineate the prospecting area, reveals the deep characteristics of the ore body through drilling, uses deep ore-indicating information marks as a basis, and uses drilling and logging technology to complete the prediction and exploration of deep positioning mineral resources of hot water jet sedimentary cobalt ore. The present invention has the characteristics of quickly identifying cobalt-containing strata, providing an implementation basis for trenching and drilling deployment, and can effectively improve exploration efficiency and shorten the exploration cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a flow chart for the prediction and exploration of hot water jet sedimentary cobalt deposits;

[0020] Figure 2 This is the distribution map of hot water sedimentary rock strata in the middle section of East Kunlun;

[0021] Figure 3 This is the prediction map of cobalt mineralization in the middle section of East Kunlun;

[0022] Figure 4 This is the comprehensive anomaly analysis diagram of Tuolugou AS03;

[0023] Figure 5 This is a 1:10,000 geological map of the Tuolugou area;

[0024] Figure 6 This is a comprehensive profile of geophysical and geochemical exploration in Tuolugou area;

[0025] Figure 7 This is the profile of exploration line 116 in Tuolugou area;

[0026] Figure 8 It is a well logging curve diagram. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] According to the abnormal sections with copper-cobalt, iron-cobalt, cobalt-gold as the main elements in the 1:500,000, 1:50,000 and 1:25,000 stream sediment measurement results with good reproducibility, the present invention uses 1:5000 or 1:2000 large-scale geochemical profiles and induced polarization profiles and 1:10,000 special geological mapping results to deploy trenching in favorable sections for prospecting to expose and verify, and delineate the mineralized body or ore body; use drilling to verify and specifically delineate the ore body. Use drilling and logging technology to accurately determine the deep mineral (chemical) layer. Figure 1 This is a flow chart for the prediction and exploration of hot water jet sedimentary cobalt ore according to the present invention.

[0029] Example 1

[0030] Taking the Tuolugou cobalt-gold mine in the East Kunlun orogenic belt as an example, the method for quickly delineating the cobalt ore prospecting target area is briefly described as follows:

[0031] (1) Collect regional data to compile a distribution map of hydrothermal sedimentary rock formations and preliminarily determine the favorable mineralization areas for hydrothermal jet sedimentary cobalt deposits

[0032] There are three main types of hydrothermal sedimentary rocks: hydrothermal deposits related to hot springs or heat storage activities in continental geothermal systems; hydrothermal sedimentary rocks related to regional geothermal anomalies and produced in sedimentary rock systems, related to volcanic activities; and hydrothermal sedimentary rocks produced in volcanic-sedimentary rock systems. Based on the current cobalt mineralization facts in the East Kunlun orogenic belt, it is preliminarily believed that hydrothermal sedimentary rocks are related to volcanic activities. The hydrothermal sedimentary rock strata related to volcanic activities in the East Kunlun mineralization belt in Qinghai are distributed from old to new: Jinshuikou Group, Nachitai Group, Wanbaogou Group, Qimantag Group, and Haraguole Group.

[0033] The main exposed strata in the Tuolugou cobalt-gold mining area are the Harabayigou Formation of the Nachitai Group of the Ordovician System. Previous researchers have identified a set of quartz-albicylite in this stratum, which is a typical sodium-rich exhalative sedimentary rock. The Harabayigou Formation of the Nachitai Group is a set of coastal-shallow marine clastic rocks, volcanic rocks-carbonate rocks, which are obviously controlled by structures. The strata are distorted in strike and dip, with an overall strike of nearly east-west and dip to the north.

[0034] The 1:50,000 geological and mineral maps and 1:250,000 geological and mineral maps of the area were collected and digitized. During the digitization process, the division accuracy of the 1:50,000 original map was retained as much as possible, and the original geological boundaries were not simplified in principle. In the study area, since some areas have not carried out 1:50,000 regional geological surveys or mineral surveys, the 1:250,000 regional survey data were enlarged to a 1:50,000 scale. Some maps of the same stratigraphic unit have segment-level stratigraphic units, while other maps have only group-level units. In response to this situation, we compared the rock layers and rock combination characteristics of the inconsistent joints of different map sheets through field route geological surveys, and tried to make them coordinated and unified before splicing to form a complete geological and mineral map of the study area. Through the analysis of relevant geological and mineral data in the area by predecessors, the main strata of hydrothermal sedimentary rocks in the area were sorted out, and a stratigraphic distribution map of hydrothermal sedimentary rocks was compiled. The stratigraphic distribution map is shown in Figure 2 .

[0035] (2) Fill in the gaps according to the completeness of the collected data. Use the 1:500,000 and 1:200,000 water system survey results to extract the anomalies of the main elements such as cobalt-gold, cobalt-iron, and cobalt-copper. Combined with the distribution of hydrothermal sedimentary rock strata, compile a comprehensive prediction map of the target area, preliminarily define the prospecting target area, and use the 1:25,000 water system anomaly measurement results to further decompose the anomalies and optimize the target area.

[0036] by Figure 2 Based on the 1:200,000 / 1:500,000 water system copper-cobalt-gold combination anomaly in the area, a cobalt mineralization prediction map of the middle section of East Kunlun was compiled ( Figure 3 ) and preliminarily define the prospecting target area.

[0037] According to the East Kunlun cobalt mineralization prediction map ( Figure 3 ), and selected the Tuolugou cobalt prospecting target area for verification. The AS03 anomaly was identified in the 1:50,000 stream sediment measurement in the area, and the Tuolugou AS03 comprehensive anomaly analysis map was drawn ( Figure 4 ), the anomaly is the anomaly of the southern mineralized zone of the Tuolugou mining area, distributed from the east side of the South Valley to Tuolugou, the anomaly is mainly composed of Au and Co elements, and the element combination is mainly Ag, Bi, Pb, Zn, Cu, Ni, As elements, etc. The comprehensive anomaly is irregularly striped and distributed in a nearly east-west direction, about 14km long from east to west, about 2.0-2.5km wide from north to south, and covers an area of ​​about 35km 2 The combination of abnormal elements is very complex, and the degree of abnormal overlap of each element is good ( Figure 4 ). The main element Co and Au anomalies have significant three-level concentration zones and multiple concentration centers, and the anomaly scale and intensity are large. Among them, the Au anomaly is contained by the Co anomaly. The main element Co peak is 79.4×10 -6 , mean 20.05×10 -6, contrast value 1.32; Au peak 215×10 -9 , with a mean of 17.13×10 -9 , contrast value 3.43.

[0038] (3) Carry out 1:10,000 special geological mapping of key abnormal areas in the area ( Figure 5 ), establish a reasonable stratigraphic sequence, find out the distribution characteristics, rock layer thickness, lithology, rock combination characteristics, lithofacies combination, etc. of hydrothermal sedimentary rocks, study the mineralization of hydrothermal sedimentary rocks, and establish mineralization marker layers.

[0039] Physical property samples of the main lithologies in the area were collected and measured. The results are shown in Table 1. The veinlet-disseminated massive pyrite (stone) cobalt ore and pyrite quartz albite are characterized by medium and high resistance and high polarization, with an average polarization rate of 6.97-17.24% and an average resistivity of 872-1232Ω·M, which are the main abnormal types to be found in this area. The chlorite sericite quartz schist and quartz albite are characterized by high resistance and low polarization, with an average polarization rate of 0.72-0.74% and an average resistivity of 1141-1457Ω·M.

[0040] Table 1 Statistics of electrical and physical properties of Tuolugou rock (ore)

[0041] Lithology Number of specimens (pieces) Resistivity Ω·M Polarization % (Green mud silk cloud) quartz schist 169 1234 0.87 Quartz Sodalite 120 1076 0.70 Pyritized quartz albite 50 1232 6.97 Cobalt oxide ore 27 886 0.11 Lumpy Pyrite Cobalt Ore 43 872 17.24 Spotted Phyllite 10 162 0.88 Quartz vein 3 3500 0.61

[0042] The 1:2 kilochemical profile and 1:2 kiloelectric intermediate profile carried out on the surface of the area were used to delineate the ore bodies according to the abnormal sections of cobalt (the sections with Co elements higher than the background value of the entire profile were used as abnormal sections to delineate the ore bodies) and the abnormal sections with apparent polarizability>1.5%. Figure 6 ), the cobalt ore body was found, of which TC25 was about 32m wide and the average cobalt grade was 0.058×10 -2 , up to 0.45×10 -2 .

[0043] (4) Deep verification by drilling Figure 7 ), chemical samples are taken during the drilling project to analyze the Co element value. The ore body is defined as the one with a cut-off grade greater than 0.02%. At the same time, the induced polarization logging curve ( Figure 8 ) Discover the missed mineralized layer (combined with the results of the physical properties of rocks and ores in the area, the area with an apparent polarizability between 6.97% and 17.24% may be a mineralized layer. The degree of mineralization can also be judged by the relative size of the apparent polarizability value. The higher the apparent polarizability value, the stronger the mineralization). Compare the lithology, ore body thickness and grade changes between adjacent boreholes ( Figure 7 ), and then comprehensively analyze the spatial distribution law of the strata in the entire survey area and the change law of the mineralized (mineralized) layer.

[0044] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0045] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for prospecting hot water jet sedimentation type cobalt ore, characterized in that: The following steps are involved: Step 1: Collect regional data to compile a distribution map of hydrothermal sedimentary rock formations, and preliminarily determine the favorable mineralization areas of hydrothermal jet sedimentary cobalt deposits; Step 2: Based on the results of the 1:500,000 or 1:200,000 stream sediment measurement, compile a cobalt element anomaly map, combine it with the hydrothermal sedimentary rock strata distribution map, compile a comprehensive prediction map of the target area, and use the 1:50,000 or 1:25,000 stream sediment measurement results to further decompose the anomaly and optimize the target area; Step 3: Based on step 2, carry out special investigation in the target area, use 1:10,000 special geological mapping to establish the marker layer, and then use induced polarization profile and / or geochemical profile to conduct preliminary verification of the target area and delineate the ore body; Step 4: Based on step 3, deep verification is carried out by drilling, and deep mineral layers are determined by borehole electrical logging. By comparing the lithology and rock layer thickness between different boreholes, a comprehensive analysis of the change patterns of the strata and mineral-bearing layers in the entire survey area is conducted to carry out a comprehensive evaluation of the cobalt mines in the area; The cobalt element anomaly map in step 2 includes a cobalt-gold element combination anomaly map, a cobalt-iron-lead-zinc element combination anomaly map, and a cobalt-copper element combination anomaly map; In step 3, the induced polarization abnormal area with low resistance and high polarization characteristics is used to delineate the ore body in the induced polarization profile results; the section where the Co element of the geochemical profile is higher than the background value of the entire profile is used as the abnormal section to delineate the ore body; In step three, the ore body is delineated based on the apparent polarizability of 6.97-17.24% in the induced polarization profile and / or geochemical profile results, and the scale of the induced polarization profile and / or geochemical profile is 1:2000 or 1:5000.

2. The method for exploring hot water jet deposition type cobalt ore according to claim 1, characterized in that: Step 1: Collect regional 1:50,000 geological and mineral maps and / or 1:250,000 geological and mineral maps, and compile a hydrothermal sedimentary rock stratigraphic distribution map in combination with field route geological surveys.

3. The method for exploring hot water jet deposition type cobalt ore according to claim 1, characterized in that: In step 4, chemical samples are taken from the drilling project to analyze the Co element value. The ore body is defined as one with a cut-off grade greater than 0.02%.

4. The method for exploring hot water jet deposition type cobalt ore according to claim 1, characterized in that: In step 4, the natural potential curves obtained by borehole logging have no obvious differences in various rock and mineral layers, and there are obvious low-resistance and high-polarization anomalies in known mineralized layers to verify the ore body.

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