阅读说明：本技术 一种火山岩型铀矿深部成矿潜力的评价方法 (Evaluation method for deep mineralization potential of volcanic rock type uranium ore ) 是由 王勇剑 聂江涛 于 2021-06-07 设计创作，主要内容包括：本发明属于地质勘查领域,具体公开一种火山岩型铀矿深部成矿潜力的评价方法,包括：步骤(1)、选择典型矿床进行样品采集及光片制作；步骤(2)、确定铀矿物组合类型；步骤(3)、构建铀矿物组合空间垂向变化趋势模型并对深部铀矿成矿潜力进行快速评价。本发明方法通过对典型火山岩型铀矿床矿石矿物、蚀变矿物组合空间变化特征研究并总结其共性规律,建立火山岩型矿床、矿带的铀矿物组合空间变化预测模型,以用于快速评价火山岩型铀矿区深部成矿潜力。(The invention belongs to the field of geological exploration, and particularly discloses an evaluation method for deep mineralization potential of volcanic rock type uranium ores, which comprises the following steps: selecting a typical deposit to carry out sample collection and polished section manufacturing; determining a uranium mineral combination type; and (3) constructing a vertical variation trend model of a uranium mineral combination space and quickly evaluating the mineralization potential of the deep uranium ore. According to the method, a prediction model of the uranium mineral combination space change of the volcanic rock type ore deposit and the ore belt is established by researching the typical volcanic rock type uranium deposit ore mineral and altered mineral combination space change characteristics and summarizing the common law of the typical volcanic rock type uranium deposit ore mineral and altered mineral combination space change characteristics so as to be used for rapidly evaluating the deep mineralization potential of the volcanic rock type uranium deposit area.)

1. The evaluation method for deep mineralization potential of the volcanic-type uranium ore is characterized by comprising the following steps of:

selecting a typical deposit to carry out sample collection and polished section manufacturing;

determining a uranium mineral combination type;

and (3) constructing a vertical variation trend model of a uranium mineral combination space and quickly evaluating the mineralization potential of the deep uranium ore.

2. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 1, wherein the sample collection in the step (1) is specifically as follows: and sampling uranium ores in different middle sections or elevations of a drilled hole or a gallery, and preliminarily determining the mineralization grade of the uranium ores according to the measurement result of the directional radiometer.

3. The method for evaluating deep mineralization potential of the volcanic-type uranium ore according to claim 1, wherein the slide making in the step (1) is specifically as follows: the collected samples were sent to a sample preparation chamber which was ground to a rock slice thickness of 0.03cm for microscopic mineralogical observation.

4. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 1, wherein the step (2) comprises the following steps:

step (2.1), preliminarily judging the uranium mineral combination type in the polished section;

and (2.2) carrying out chemical composition determination on the uranium minerals which are not identified in the light sheet and determining the uranium mineral combination type.

5. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 4, wherein the step (2.1) is specifically as follows: grinding an ore sample collected in the field into a polished section, determining the stage and the stage of an ore formation stage of uranium by using an ore phase microscope and a polarization microscope in combination with the field geological research result, finding out mineral symbiotic combinations in the uranium ore, preliminarily judging possible uranium minerals, and determining suspected uranium minerals in each slice by using a marker pen.

6. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 4, wherein in the step (2.2), an electron probe EPMA and a scanning electron microscope SEM are combined for chemical composition measurement, and a uranium mineral combination type is determined.

7. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 4, wherein the step (2.2) further comprises: and (3) carrying out micro-area component analysis by adopting a laser ablation inductively coupled plasma mass spectrometry technology LA-ICP-MS.

8. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 4, wherein the step (2.2) further comprises: and combining the back scattering image and the cathodoluminescence image to perform chemical composition measurement and determine the uranium mineral combination type.

9. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 4, wherein the step (2.2) of determining and defining the types of the uranium mineral combinations comprises finding out mineralogical characteristics of different types of uranium minerals, determining the uranium mineral combinations and the respective specific gravities of the uranium mineral combinations in ore bodies at each middle section or elevation, and analyzing and comparing differences in the main trace element contents and occurrence rules of the different types of uranium minerals in the uranium ore at different elevations.

10. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 9, wherein the mineralogical characteristics comprise morphology, particle size, relative content, mineral inclusion condition and the like of the uranium mineral.

11. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 1, wherein the step (3) is specifically as follows: combining the change laws of ore-containing structures, hydrothermal vein bodies, altered surrounding rocks and the like of different middle sections or elevations of the sections of the drill holes or the tunnels from the upper part of the ore deposit to the lower part of the ore deposit, systematically summarizing different middle section altered mineral combination types and uranium mineral combination types, constructing a vertical variation trend graph of the uranium mineral combination, and rapidly judging the ore-forming potential of deep uranium mineralization according to the variation trend of the uranium mineral combination.

12. The method for evaluating the deep mineralization potential of the volcanic-type uranium ore according to claim 11, wherein the evaluation criteria of the deep uranium ore mineralization potential in the step (3) are as follows: if a certain ore band or ore body group is mainly uranium mineral combination of uraninite or uraninite and uranite from a shallow part to a deep part and the content of titanium and uranium ore is low, the ore band or ore body group possibly has better extension in the deep part; if a uranium mineral combination change rule of main uranium asphalt ore (shallow part) → uranium asphalt ore + uranite + titanium uranium ore (middle part) → uranium titanium ore (deep part) exists in a certain ore zone or ore body group from the shallow part to the deep part, the ore zone or ore body group has a complete vertical mineralization zonal from an ore head to an ore tail, and the mineralization potential of the ore zone or ore body in the deep part is limited; in the second case, if the uranium mineral combination suddenly changes to a uranium mineral combination of uraninite or uraninite + uranite at a certain depth, it indicates that the ore band or ore body is extinguished and reproduced, i.e., a new ore band or ore body group is found at a deep position.

Technical Field

The invention belongs to the field of geological exploration, and particularly relates to an evaluation method for deep mineralization potential of volcanic rock type uranium ores.

Background

Volcanic rock type uranium ore is one of four major types of uranium ore in China, and the uranium ore exploration work of over 60 years for this type of ore deposit is carried out in China. With the gradual depletion of surface ores and shallow ores, especially large and ultra-large uranium ore deposits are rarely found on the surface or shallow parts, in order to meet the increasing demand of the China on uranium resources, the 'attacking depth and blindness' and 'exploring side and touching bottom' taking hidden and deep ores as exploration targets become the main points of exploration in the implementation of deep exploration plans in China at present. Deep bodies are buried underground and are particularly difficult to work with geological signatures and techniques common to mineralisation beyond 500 m. Hydrothermal deposits generally exhibit relatively pronounced horizontal and vertical zones of altered segregation, with specific combinations of ore minerals, altered minerals and elements in different altered zones. For example, VMS-type lead-zinc ores have a tendency to change from upper copper ores to lower lead-zinc ores; skarn-type ores have a transition tendency from a central band of molybdenum, copper, to a remote band of lead-zinc; in an russian Streltsovka type uranium deposit, there is a uranium mineral composition change law from shallow to deep in uraninite + molybdenite (800m shallow) → uraninite + uranite (800-. Therefore, the change rule of the combination of the specific types of alterations on the space can be used as an important mark for predicting the mineralization potential of the deep ore body and the ore deposit.

Based on the mature mineralization zonation theory, the method is based on the actual characteristics of the volcanic rock type uranium ore in China for carding optimization, and establishes a prediction model of the uranium mineral combination space change of the volcanic rock type ore deposit and the ore zone by researching the ore mineral and altered mineral combination space change characteristics of the typical volcanic rock type uranium deposit and summarizing the common law of the ore mineral and altered mineral combination space change characteristics, so that the method can be used for rapidly evaluating the deep mineralization potential of the volcanic rock type uranium ore zone.

Disclosure of Invention

The invention aims to provide an evaluation method of deep mineralization potential of a volcanic rock type uranium ore, which is used for rapidly evaluating the deep mineralization potential of a volcanic rock type uranium ore region by researching the combination space change characteristics of ore minerals and altered minerals of a typical volcanic rock type uranium ore deposit and summarizing the common law of the change characteristics and establishing a prediction model of the combination space change of the uranium minerals of the volcanic rock type ore deposit and an ore belt.

The technical scheme for realizing the purpose of the invention is as follows: a method for evaluating deep mineralization potential of a volcanic-type uranium ore comprises the following steps:

selecting a typical deposit to carry out sample collection and polished section manufacturing;

determining a uranium mineral combination type;

and (3) constructing a vertical variation trend model of a uranium mineral combination space and quickly evaluating the mineralization potential of the deep uranium ore.

The sample collection in the step (1) is specifically as follows: and sampling uranium ores in different middle sections or elevations of a drilled hole or a gallery, and preliminarily determining the mineralization grade of the uranium ores according to the measurement result of the directional radiometer.

The optical sheet manufacturing in the step (1) specifically comprises the following steps: the collected samples were sent to a sample preparation chamber which was ground to a rock slice thickness of 0.03cm for microscopic mineralogical observation.

The step (2) comprises the following steps:

step (2.1), preliminarily judging the uranium mineral combination type in the polished section;

and (2.2) carrying out chemical composition determination on the uranium minerals which are not identified in the light sheet and determining the uranium mineral combination type.

The step (2.1) is specifically as follows: grinding an ore sample collected in the field into a polished section, determining the stage and the stage of an ore formation stage of uranium by using an ore phase microscope and a polarization microscope in combination with the field geological research result, finding out mineral symbiotic combinations in the uranium ore, preliminarily judging possible uranium minerals, and determining suspected uranium minerals in each slice by using a marker pen.

And (2.2) combining an Electronic Probe (EPMA) and a Scanning Electron Microscope (SEM) to perform chemical composition determination and determine the uranium mineral combination type.

The step (2.2) further comprises: and (3) carrying out micro-area component analysis by adopting a laser ablation inductively coupled plasma mass spectrometry technology LA-ICP-MS.

The step (2.2) further comprises: and combining the back scattering image and the cathodoluminescence image to perform chemical composition measurement and determine the uranium mineral combination type.

And (2.2) determining and determining the types of the uranium mineral combinations by chemical composition determination, wherein the step of determining the mineralogical characteristics of different types of uranium minerals, determining the uranium mineral combinations and the respective specific gravities of the uranium mineral combinations in the ore bodies at each middle section or elevation, and analyzing and comparing the differences in the main trace element contents and occurrence rules of the different types of uranium minerals in the uranium ores at different elevations.

The mineralogy characteristics comprise the morphology, the granularity and the relative content of the uranium minerals, the inclusion condition of the minerals and the like.

The step (3) is specifically as follows: combining the change laws of ore-containing structures, hydrothermal vein bodies, altered surrounding rocks and the like of different middle sections or elevations of the sections of the drill holes or the tunnels from the upper part of the ore deposit to the lower part of the ore deposit, systematically summarizing different middle section altered mineral combination types and uranium mineral combination types, constructing a vertical variation trend graph of the uranium mineral combination, and rapidly judging the ore-forming potential of deep uranium mineralization according to the variation trend of the uranium mineral combination.

The evaluation criterion of the ore forming potential of the deep uranium ore in the step (3) is as follows: if a certain ore band or ore body group is mainly uranium mineral combination of uraninite or uraninite and uranite from a shallow part to a deep part and the content of titanium and uranium ore is low, the ore band or ore body group possibly has better extension in the deep part; if a uranium mineral combination change rule of main uranium asphalt ore (shallow part) → uranium asphalt ore + uranite + titanium uranium ore (middle part) → uranium titanium ore (deep part) exists in a certain ore zone or ore body group from the shallow part to the deep part, the ore zone or ore body group has a complete vertical mineralization zonal from an ore head to an ore tail, and the mineralization potential of the ore zone or ore body in the deep part is limited; in the second case, if the uranium mineral combination suddenly changes to a uranium mineral combination of uraninite or uraninite + uranite at a certain depth, it indicates that the ore band or ore body is extinguished and reproduced, i.e., a new ore band or ore body group is found at a deep position.

The invention has the beneficial technical effects that:

1. the evaluation method for the deep mineralization potential of the volcanic rock type uranium ore provided by the invention carries out prediction evaluation on the deep mineralization potential of known ore deposits (such as Zhoushan ore deposits, Shannan ore deposits, Yunjian ore deposits and the like), and provides a basis for deep prospecting and working deployment of the uranium ore in the Yangshan ore deposit.

2. The evaluation method for the deep mineralization potential of the volcanic-type uranium ore is based on microscopic observation and a micro-area geochemistry analysis method, and the deep mineralization potential of the volcanic-type uranium ore is predicted and evaluated by utilizing the spatial change characteristics of the uranium ore, so that the method is economic, rapid and wide in application range.

3. The evaluation method for the deep mineralization potential of the volcanic rock type uranium ore provided by the invention carries out related prediction evaluation on the deep parts of a plurality of uranium ore deposits of the opposite volcanic rock type uranium ore field, and the evaluation method is more consistent with the actual exploration and exploitation result.

4. The evaluation method for the deep mineralization potential of the volcanic type uranium ore provided by the invention is suitable for most volcanic type uranium ore mineralization areas in south China.

5. The evaluation method for deep mineralization potential of the volcanic rock type uranium ore provided by the invention has important significance for deepening the volcanic rock type uranium ore exploration method and comprehensively carrying out comprehensive prediction and evaluation on the deep uranium ore.

Drawings

FIG. 1 shows a vertical variation trend of a No. 4 cambium uranium deposit mineral aggregate;

fig. 2 a sectional view of a exploration line in a uranium deposit in yohima 57;

FIG. 3 is a vertical variation trend diagram of altered mineral combinations of intercropped uranium deposits;

fig. 4 is a section view of exploration line No. 4 of an intercropping uranium deposit.

Detailed Description

The present invention will be described in further detail below by taking ore belt No. 4 and Yunjiashan deposit of the Renshan uranium ore field as an example.

Example 1 Zhoushan deposit No. 4 belt

The invention provides an evaluation method for deep mineralization potential of a volcanic rock type uranium ore, which comprises the following steps:

step (1), selecting a typical deposit to collect a sample and manufacturing a polished section

The uranium ore body developed in the volcanic rock type uranium ore deposit in China generally takes a group vein type as a main part, and is different from a large vein type in a granite type uranium ore (such as a cotton pit deposit), and the uranium ore body is mostly in a group and a band, so that one relatively continuous and concentrated uranium ore band in a typical ore deposit is preferably selected to carry out system sampling. The method fully utilizes drilling section and plane data of a typical ore deposit, can carry out field work according to a drilling core or tunnel section according to the specific condition of the ore deposit, carries out systematic uranium ore sampling work in different middle sections or elevations of the drilling or the tunnel, preliminarily determines the mineralization grade of the uranium ore according to the measurement result of a gamma directional radiometer, ensures that the uranium grades of mineralized bodies with different elevations are consistent or approximate as much as possible, and simultaneously considers the change rules of geological characteristics of ore deposit ore-containing structures, altered surrounding rocks and the like. After the sampling work of the system is finished, the sampled product is polished by a system polished section or a polished section for subsequent under-mirror observation and experiment.

The method is characterized in that the Zhoujia uranium deposit with the deepest mining depth is selected as a research target. The Zhoujia deposit is a uranium deposit with the largest reserve in the Xiangshan uranium deposit, and the deposit has 1, 2, 3, 4, 14 and other deposit zones. The ore bodies are in a vein shape and a lens shape, and appear in groups and in bands, 482 industrial ore bodies are found, wherein the industrial ore bodies mainly comprise medium and small ore bodies, and the mineralization vertical amplitude is more than 700 m. The uranium ore samples used for the study were taken from the main ore zone of the deposit currently mined to the greatest depth: and in the No. 4 ore belt, sufficient uranium ores are respectively collected in-90 m middle section, -130m middle section, -170m middle section, -210m middle section, -250m middle section and-450 m middle section of the No. 4 ore belt tunnel, and the mineralization grade of the uranium ore is determined according to the measurement result of a gamma directional radiometer (the grade of the uranium ore can be directly given), and if the U content measurement value is more than 500ppm, the uranium ore can be determined to be in accordance with the industrial exploitation grade. In order to facilitate research, the rich ore with the U content of more than 1000ppm is selected as much as possible, and the consistent or close uranium grades of mineralized samples with different elevations are ensured.

After the sampling work of the system is finished, the selected samples which can be used as further research are sent to a grinding plate sample preparation chamber for processing, and rock optical sheets with the thickness of 0.03cm are prepared for subsequent observation and experiments.

Step (2) determining uranium mineral combination types in different middle-section or elevation uranium ore bodies

Step (2.1), preliminarily judging the uranium mineral combination type in the polished section

Grinding an ore sample collected in the field into a polished section and a light slice, determining the stage and the stage of an ore forming stage of uranium by using an ore phase microscope and a polarization microscope in combination with the field geological research result, finding out mineral symbiotic combination in the uranium ore, preliminarily judging possible uranium minerals, and delineating suspected uranium minerals in each slice by using a marking pen.

Grinding a uranium ore sample collected in the field into a polished section or a light slice, carefully observing altered rocks, mineral combinations and structural features thereof, combining field geological phenomenon statistics, observation and under-mirror identification results of a large number of ore bodies, determining the trend that the mineralization type of the ore deposit No. four ore belts from top to bottom gradually changes from acid-altered type (mainly uranium-fluorite-brucite type) to acid-base altered type superposition type, and mainly mineralizing the ore deposit in the acid-base altered type in the deep part (-250m middle section); in the aspect of the altered mineral combination, the types of the altered mineral combination at different middle sections or elevations are not completely the same, the altered mineral types are more and more from the upper part of the ore belt to the lower part of the ore belt, and the mineral combination is more and more complex, and approximately, the altered mineral types are purple black fluorite, hydromication +/-chlorite petrochemistry +/-phosphorization +/-carbonation → hydromication +/-green mud petrochemistry +/-phosphorization +/-carbonation +/-phosphorization +/-sodiostronic +/-hematite mineralization → hydromication +/-chlorite petrochemistry +/-phosphorization +/-sodiostronic +/-small-amount carbonation +/-sodiostronic hematite mineralization +/-hematite mineralization.

Step (2.2) of carrying out chemometric measurements on uranium minerals not identified in the slide and of determining the type of uranium mineral combination

On the basis of the detailed observation under field and indoor mirrors and the summary of the mineralization and alteration rules, a testing means combining an Electronic Probe (EPMA) and a Scanning Electron Microscope (SEM) is adopted to carry out further chemical component determination on suspected uranium minerals or unidentified uranium minerals in samples defined from sample light sheets or light sheets collected at different depths and elevations and to determine the uranium mineral combination type. Through combination of a Back Scattering (BSE) image and a Cathodoluminescence (CL) image, the ore at the upper part (which refers to-90 m middle section and-130 m middle section) of an ore belt is mainly composed of uraninite and thorium-containing uraninite, and a small amount of uraninite is found, wherein the uraninite and the thorium-containing uraninite exist in a dip-dyed-micro vein aggregate and account for 90-95% of the total amount of uranium ore, and the uraninite exists in a granular and dispersed form and accounts for 5-10% of the total amount of uranium ore; the types and components of uranium minerals in the middle part of an ore deposit (the middle part of-170 m and the middle part of-210 m) are gradually increased and complicated, but the general population is mainly thoriated uranite, the content of the transuranite is obviously increased, and a large amount of uranites and thoriated uranites appear, wherein the uranites and the thoriated transuranites coexist with the transuranites in a kidney-shaped, dip-dyed particle or aggregate form, and account for about 30-50% of the total amount of the uranium minerals, the transuranites are in a sheet-shaped and dip-dyed aggregate form and account for about 30-45% of the total amount of the uranium minerals, and the rest uranium minerals (such as the uranites and the thoriated uranites) account for less than 20%; in the deep part of the ore deposit (-250m middle section), the uranium minerals mainly comprise the uranium titanium minerals, and part of thoriated uraninite and thorium thorite are found, wherein the uranium titanium minerals mainly exist in a dip-dyed state and account for about 75-90% of the total amount of the uranium minerals, and the rest of the uranium minerals mainly comprise the uranium asphalt minerals and the thoriated uranium asphalt minerals and account for about 10-25% of the total amount of the uranium minerals. Generally, the ore has a tendency of reducing the uranium and bitumen ores and increasing the uranium and titanium ores from the shallow part to the deep part, and the content of thorium minerals and thorium-containing minerals in the intermediate ores of-170 m, -210m and-250 m is obviously higher. In the middle section of-450 m, the uranium minerals mainly include two uranium minerals, namely (thorium-containing) uraninite and titanium uranium ore, the content proportion of the (thorium-containing) uraninite is obviously increased, the total uranium mineral content is over 75 percent, the titanium uranium ore accounts for about 20 percent of the total uranium minerals, and a small amount of uranite and uranthorite are additionally arranged.

Step (3) constructing a vertical variation trend model of uranium mineral combination space and rapidly evaluating the mineralization potential of deep uranium ores

According to the uranium minerals, altered minerals, main associated metal types and the like which develop in different middle sections, the altered mineral combination types and the uranium mineral combination types in different middle sections or elevations are systematically summarized, and a uranium mineral combination change rule that from the upper part of a ore belt to the lower part of the ore belt (from the middle section of (-90m to the middle section of-250 m) is mainly (shallow part) → uranite + titanium uranium ore (middle part) → titanium uranium ore (deep part)) exists, the rule is basically consistent with the change rule of the uranium mineral combination in the vertical direction of the russian Streltsovka volcanic uranium ore deposit, and the uranium mineralization strength of the ore deposit in the deep part is obviously reduced or completely disappears. Based on this established fact or phenomenon, it is presumed that the ore band or ore body group in the Zhoujiashan No. 4 band from-90 m to-250 m has a more complete mineralization zonal from the mine head to the mine tail, indicating that the ore band or ore body has a limited mineralization potential in deep portions. However, in the middle section of-450 m, the uranium minerals are converted into uranium mineral combinations with uranium bituminous ore as the main uranium and titanium ore, the content of the uranium bituminous ore is obviously increased, and therefore the extinction reproduction of ore belts or ore body groups is suggested, namely new ore belts or ore body groups are found at deep parts, and probably because the front edges of the deep ore belts or ore body groups are superposed on the tail parts of the upper ore belts or ore bodies.

Based on the knowledge, vertical variation trend graphs of the uranium mineral combination and the altered mineral combination in No. 4 zones of the Zhoushan deposit are constructed for the first time, the types of the mineral-element combination are shown in Table 1, and the vertical variation trend graph of the altered mineral combination is shown in FIG. 1.

TABLE 1 Zhoujiashan uranium deposit No. 4 ore belt different middle section mineral-element combination types

As can be seen from table 1 and fig. 1, there may be another deep extended portion of ore band or ore body group not revealed by engineering exploration below the-450 m mid section of the ore deposit, indicating that there is still a large uranium mineralization potential deep in the zhoujia ore deposit.

Fig. 2 shows a survey line of a uranium deposit in zhou shan 57, and it can be seen that the actual drilling results also show that more industrial ore bodies are still revealed in the middle of the-450 m to-570 m zone four. Therefore, the evaluation method is consistent with the actual exploration and exploitation result, and has better popularization and application potential.

Example 2 interplanar deposits

Step (1), selecting a typical deposit to collect a sample and manufacturing a polished section

Another example of a study is the interplanar deposit in the east of the facies mountain field. The Yunjian deposit is the only typical alkali-assisted uranium deposit in the eastern region of the Hetian uranium deposit field, is located in the eastern region of the Hetian uranium deposit field, is the most typical alkali-assisted uranium deposit in the deposit field, and is generally low in ore grade. The ore body is mainly distributed in the dense fractured zone of the main fracture, and the ore body is stable, large in scale and good in continuity, as shown in figure 4. Uranium ore samples for research are collected from 445m middle sections, 315m middle sections and 265m middle sections of tunnels, and the mineralization grade of the uranium ore is determined according to the measurement result of a gamma directional radiometer (the grade of the uranium ore can be directly given), if the U content measurement value is more than 500ppm, the uranium ore which accords with the industrial exploitation grade can be determined, and the uranium grades of the collected mineralization samples with different elevations are ensured to be consistent or close. For mining reasons, ore samples were not collected in the middle sections 215m and 165m deep sections.

After the sampling work of the system is finished, the selected samples which can be used as further research are sent to a grinding plate sample preparation chamber for processing, and rock optical sheets with the thickness of 0.03cm are prepared for subsequent observation and experiments.

Step (2) determining uranium mineral combination types in different middle-section or elevation uranium ore bodies

Step (2.1), preliminarily judging the uranium mineral combination type in the polished section

Grinding an ore sample collected in the field into a polished section and a light slice, determining the stage and the stage of an ore forming stage of uranium by using an ore phase microscope and a polarization microscope in combination with the field geological research result, finding out mineral symbiotic combination in the uranium ore, preliminarily judging possible uranium minerals, and delineating suspected uranium minerals in each slice by using a marking pen.

Firstly, grinding a uranium ore sample collected in the field into polished sheets or optical sheets, carefully observing altered rocks, mineral combinations and structural features thereof, combining field geological phenomenon statistics, observation and under-mirror identification results of a large number of ore bodies, determining that the altered mineral combination types of the ore deposit at different middle sections or elevations are basically consistent, and ensuring that the illite is weaker and weaker until the ore deposit disappears from the upper part of the ore deposit to the lower part of the ore deposit.

Step (2.2) of carrying out chemical constituent determination on unidentified uranium minerals in the slide and determining the type of uranium mineral combination

On the basis of the detailed observation under field and indoor mirrors and the summary of the mineralization and alteration rules, a testing means combining an Electronic Probe (EPMA) and a Scanning Electron Microscope (SEM) is adopted to carry out further chemical composition determination on suspected uranium minerals or unidentified uranium minerals in samples defined from sample light sheets or light sheets collected at different depths and elevations and to determine the uranium mineral combination type. By combining the back-scattered (BSE) image and the Cathodoluminescence (CL) image, it was ascertained that the ore above the ore band (in the middle of 445 m) was mainly uranite and uranite (65%), with a small amount of (silicon-containing) titanium-uranium ore (35%), in addition to a small amount of calcium-uranium-mica and dispersed uranium; the uranium mineral types in the middle (315m middle section) of the ore deposit mainly include uranite and (silicon-containing) titanium uranium ore, the content of the titanium uranium ore is obviously increased, and a large amount of uranite and thorium uranite also appear, wherein the uranite exists in the form of renal sphere and dip-dyed particles, and accounts for about 30% of the total amount of the uranium minerals, and the (silicon-containing) titanium uranium ore is in the form of sheets and needles and accounts for about 40-50% of the total amount of the uranium minerals; in the lower part of the deposit (mid 265 m), the uranium minerals were found to be predominantly (over 80%) titanium-containing uranium ores, whereas thorium-containing uranites and uranites account for only a small amount (< 20%). Generally, there is a tendency that uranium bituminous ore decreases and uranium titaniferous ore increases from the shallow part to the deep part, as shown in fig. 3.

Step (3) constructing a vertical variation trend model of uranium mineral combination space and rapidly evaluating the mineralization potential of deep uranium ores

According to the uranium minerals, altered minerals, main associated metal types and the like which develop in different middle sections, the system summarizes the altered mineral combination types and the uranium mineral combination types of different middle sections or elevations of the intercropped deposit, and finds out the uranium mineral combination change law from the upper part to the lower part (from the middle section of 445m to the middle section of 265 m) of the deposit, wherein the uranium mineral combination change law exists, namely the uranium bituminous ore is mainly titanium uranium ore (shallow part) → the uranium bituminous ore + the titanium uranium ore (middle part) → the uranium ore is mainly titanium uranium ore (deep part), the total uranium mineral content of the uranium bituminous ore in the middle section of 445m in the shallow part is about 50%, the uranium mineral content is reduced to 15% in the middle section of 265 in the deep part, and the uranium titanium ore is increased to more than 80% from about 30%. This is similar to the change law of example 1 (zhoushan deposit No. 4 band), i.e., the change tendency from shallow to deep with a decrease in uranite and an increase in uranite.

Based on the knowledge, a vertical variation trend graph of the uranium mineral combination and the altered mineral combination of the intercropping deposit is preliminarily constructed, the mineral-element combination is shown in table 2, and the vertical variation trend graph of the altered mineral combination is shown in fig. 3.

TABLE 2 different middle stage mineral-element combination types of intercropping deposits

Table 2 and fig. 3 show that the 265m middle section may already belong to the tail part of the deposit or ore body, and the deep part has little mineralization potential.

As shown in fig. 4, the actual drilling and pit-exploring results also show that ore bodies are only exposed in the middle of 165m and the middle of 215m, and the exploration data shows that the grade and thickness of the ore bodies also show a trend of getting weaker and weaker, and no mineralization is shown towards the deep part. This is substantially consistent with the predicted results by the evaluation method of the present invention, further demonstrating the effectiveness of the evaluation method of the present invention.

The invention has been described in detail with reference to the drawings and the two embodiments, but the invention is not limited to the embodiments described above, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the invention. The prior art can be adopted for the content which is not described in detail in the invention.