CN103886382A - Volcanic rock type uranium mine target optimization method based on element geochemical abnormity - Google Patents

Abstract

The present invention relates to a method for optimizing target areas of volcanic rock type uranium deposits based on geochemical anomalies, which sequentially includes: 1) collection or collection of elemental geochemical data; 2) compilation of single-element geochemical anomaly maps; 3) ore point projection transformation; 4 ) Screening of indicator elements; 5) Compilation of geochemical equivalence maps of thorium-uranium ratios; 6) Compilation of geochemical anomalies maps of uranium elements, auxiliary indicator elements, and thorium-uranium ratios and projection transformation; 7) Judgment of abnormal forms; 8) Judgment Level of uranium mineralization prospect target area. The invention is applicable to multiple ore-forming belts and prediction areas of volcanic rock type in the whole country, and has wide coverage, high effectiveness, strong applicability and good accuracy. The invention has clear indicating elements, strong operability, standardizes the evaluation method flow, improves evaluation efficiency, and ensures the objectivity of research results.

Description

Target selection method for volcanic rock-type uranium deposits based on elemental geochemical anomalies

technical field

The invention relates to a volcanic rock type uranium ore target selection method based on elemental geochemical anomalies, in particular to a volcanic rock type uranium ore target area optimization method suitable for volcanic rock type resource potential evaluation and uranium prospect target area prediction.

Background technique

Elemental geochemical method is an important and effective method for geochemical prospecting of uranium ore. This method evaluates the ore-forming potential of uranium ore through the abnormal content of ore-forming elements and associated elements in the region. Uranium deposits in my country are mainly divided into four types, including granite type, volcanic rock type, sandstone type and carbon-silica mudstone type. Volcanic rock type uranium deposits are one of the most important types among the four major types of uranium deposits in my country. In the evaluation of elemental geochemical anomalies In the work, in the past, there was no clear indicator element and its screening method for ore prospecting, and there was no clear method for selecting uranium ore-forming target areas based on geochemical anomalies, which directly affected the utilization level of geochemical data and the effect of uranium ore potential evaluation , so it is urgent to provide a new method for optimizing the target area of volcanic rock type uranium ore.

Contents of the invention

The technical problem to be solved by the present invention is to provide a volcanic rock-type uranium ore target area optimization method based on geochemical anomalies with high effectiveness, strong applicability and good accuracy, which has clear indicator elements and strong operability.

In order to solve the above-mentioned technical problems, the present invention provides a volcanic rock-type uranium ore target optimization method based on elemental geochemical anomalies, which includes the following steps in sequence:

1) Choose a scale of 1:50,000 to 1:200,000 to deploy a survey network in the prediction area, collect water sediment samples, and obtain geochemical data, or collect elemental geochemical data at a scale of 1:50,000 to 1:200,000;

2) Compilation of single-element geochemical anomaly maps;

Compile a single-element geochemical equivalence map of all geochemical analysis elements in the prediction area;

3) Mining point projection transformation;

The location of known volcanic-type uranium deposits in the prediction area is projected and transformed in the form of a point file using the same projection parameters as the digital geological map of the predicted area. In the prediction area without known volcanic-type uranium deposits, the volcanic-type uranium deposits and mineralization points Use the same projection parameters as the digital geological map of the prediction area to carry out projection transformation in the form of point files;

4) Screening of indicating elements;

The main ore-forming element uranium is selected as the main indicator element, and the auxiliary indicator elements are screened by the profile correlation analysis method;

5) Compile the geochemical equivalent map of thorium-uranium ratio;

6) Compile the geochemical anomaly map of uranium elements, auxiliary indicator elements, and thorium-uranium ratios, and use the same projection parameters as in 3) for projection transformation;

In the geochemical equivalent map of uranium elements, the area where the cumulative frequency of uranium elements is 25% to 70% is marked as uranium element anomaly, and the uranium element geochemical anomaly map is obtained;

In the geochemical equivalence map of auxiliary indicator elements, the area with cumulative frequency of auxiliary indicator elements ≥ 70% is marked as auxiliary element anomaly, and the geochemical anomaly map of auxiliary indicator elements is obtained;

In the thorium-uranium ratio geochemical isovalue map, the region with a thorium-uranium ratio ≤ 3 is calibrated as a thorium-uranium ratio geochemical anomaly, and a thorium-uranium ratio geochemical anomaly map is obtained;

7) Judging the abnormal form:

In the geochemical anomaly map of uranium elements, auxiliary indicator elements, and thorium-uranium ratio after the above projection, compare the digital geological map, keep the anomalies that meet the following characteristics, and obtain the geochemical anomalies of uranium elements, auxiliary indicator elements, and thorium-uranium ratio after processing picture;

① The abnormal shape is face-like or bead-like;

②The location of abnormal distribution is consistent with the distribution area of favorable intervals of intermediate-acid volcanic rock mineralization;

8) In contrast to the digital geological map of geological prediction, in the processed uranium element, auxiliary indicator element and thorium-uranium ratio geochemical anomaly map, the uranium element anomaly is superimposed on the thorium-uranium ratio geochemical anomaly and more than one auxiliary indicator element anomaly The area that overlaps and overlaps with two or more favorable metallogenic elements predicted by geology is judged as the first-level uranium mineralization prospect target area;

The area where the uranium anomaly outside the first-level uranium metallogenic prospect target area and the thorium-uranium ratio geochemical anomaly outside the first-level uranium metallogenic prospect target area overlaps and overlaps with a favorable mineralization element predicted by geology is judged as Secondary uranium mineralization prospect target area;

The uranium element anomalies outside the primary and secondary uranium mineralization prospect areas are judged as the tertiary uranium mineralization prospect target areas.

The profile correlation analysis method is:

When there are known volcanic-type uranium deposits, the known volcanic-type uranium deposits are superimposed on the compiled single-element geochemical equivalence map, and a linear section is drawn at the position where the known volcanic-type uranium deposits pass, and the length of the section is 1 Kilometers to 10 kilometers, conduct correlation analysis according to 50-90% correlation, and take the three elements with the highest correlation as auxiliary indicator elements;

When there is no known volcanic-type uranium deposit, superimpose the known volcanic-type uranium deposits and mineralization points on the compiled single-element geochemical equivalence map, and draw Linear profile, the length of the profile is 1 km to 10 km, the correlation analysis is carried out according to the correlation degree of 50-90%, and the three elements with the highest correlation degree are taken as the auxiliary indicator elements;

When there are no known volcanic rock-type uranium deposits, ore points, and mineralization points, three elements of molybdenum, silver, fluorine, beryllium, and mercury are selected as auxiliary indicator elements.

The invention is applicable to multiple ore-forming belts and prediction areas of volcanic rock type in the whole country, and has wide coverage, high effectiveness, strong applicability and good accuracy.

The invention has clear indicating elements, strong operability, standardizes the evaluation method flow, improves evaluation efficiency, and ensures the objectivity of research results.

Detailed ways

The present invention comprises the following steps in turn:

1) Choose a scale of 1:50,000 to 1:200,000 to deploy a survey network in the prediction area, collect water sediment samples, and obtain geochemical data, or collect elemental geochemical data at a scale of 1:50,000 to 1:200,000;

2) Compilation of single-element geochemical anomaly maps;

Compile a single-element geochemical equivalence map of all geochemical analysis elements in the prediction area;

3) Mining point projection transformation;

The location of known volcanic-type uranium deposits in the prediction area is projected and transformed in the form of a point file using the same projection parameters as the digital geological map of the predicted area. In the prediction area without known volcanic-type uranium deposits, the volcanic-type uranium deposits and mineralization points Use the same projection parameters as the digital geological map of the prediction area to carry out projection transformation in the form of point files;

4) Screening of indicating elements;

The main ore-forming element uranium is selected as the main indicator element, and the auxiliary indicator elements are screened by the profile correlation analysis method;

5) Compile the geochemical equivalent map of thorium-uranium ratio;

6) Compile the geochemical anomaly map of uranium elements, auxiliary indicator elements, and thorium-uranium ratios, and use the same projection parameters as in 3) for projection transformation;

In the geochemical equivalent map of uranium elements, the area where the cumulative frequency of uranium elements is 25% to 70% is marked as uranium element anomaly, and the uranium element geochemical anomaly map is obtained;

In the geochemical equivalence map of auxiliary indicator elements, the area with cumulative frequency of auxiliary indicator elements ≥ 70% is marked as auxiliary element anomaly, and the geochemical anomaly map of auxiliary indicator elements is obtained;

In the thorium-uranium ratio geochemical isovalue map, the region with a thorium-uranium ratio ≤ 3 is calibrated as a thorium-uranium ratio geochemical anomaly, and a thorium-uranium ratio geochemical anomaly map is obtained;

7) Judging the abnormal form:

In the geochemical anomaly map of uranium elements, auxiliary indicator elements, and thorium-uranium ratio after the above projection, compare the digital geological map, keep the anomalies that meet the following characteristics, and obtain the geochemical anomalies of uranium elements, auxiliary indicator elements, and thorium-uranium ratio after processing picture;

① The abnormal shape is face-like or bead-like;

②The location of abnormal distribution is consistent with the distribution area of favorable intervals of intermediate-acid volcanic rock mineralization;

8) In contrast to the digital geological map of geological prediction, in the processed uranium element, auxiliary indicator element and thorium-uranium ratio geochemical anomaly map, the uranium element anomaly is superimposed on the thorium-uranium ratio geochemical anomaly and more than one auxiliary indicator element anomaly The area that overlaps and overlaps with two or more favorable metallogenic elements predicted by geology is judged as the first-level uranium mineralization prospect target area;

The area where the uranium anomaly outside the first-level uranium metallogenic prospect target area and the thorium-uranium ratio geochemical anomaly outside the first-level uranium metallogenic prospect target area overlaps and overlaps with a favorable mineralization element predicted by geology is judged as Secondary uranium mineralization prospect target area;

The uranium element anomalies outside the primary and secondary uranium mineralization prospect areas are judged as the tertiary uranium mineralization prospect target areas.

The favorable ore-forming elements for the above geological prediction are ore-hosting structure, alteration type, and ore-hosting lithology.

The scale of 1:50,000 to 1:200,000 above-mentioned first, second, and third-level prospect areas are divided according to the possibility of mineralization and the sequence of exploration work. The first-level prospect area is the most favorable uranium mineralization prospect area. The second-level prospect area is a favorable uranium ore-forming prospect area, and the third-level prospect target area is a more favorable uranium ore-forming prospect area. Further exploration work will be carried out in sequence according to the first, second, and third-level prospect areas.

The invention is applicable to the Ganhang volcanic rock type uranium metallogenic belt and other volcanic rock type multiple metallogenic belts and prediction areas in the whole country.

Claims (2)

1. the volcanic type U-ore target selection method based on geo-chemical element anomaly, comprises the following steps successively:

1) select 1:5 ten thousand～1:20 ten thousand engineer's scales to arrange survey grid in prediction district, gather sediments sample, obtain geochemistry data, or collect 1:5 ten thousand～1:20 ten thousand engineer's scale element geochemistry datas;

2) single element geochemical anomaly map establishment;

To predict district's Geochemistry analytical element planning unit element geochemistry equal-value map fully;

3) ore deposit spot projection conversion;

Adopt the projective parameter identical with prediction district digital geological map to carry out projective transformation with the form of dot file prediction known Volcanic Type Uranium Deposits position, district, do not have the prediction district of known Volcanic Type Uranium Deposits to adopt the projective parameter identical with prediction district digital geological map to carry out projective transformation with mineralization points with dot file form volcanic type U-ore point;

4) indicator element screening;

Select main ore-forming element uranium as main indicator elements, auxiliary indicator element screens by section association analysis method;

5) establishment TURA value geochemistry equal-value map;

6) establishment uranium element, auxiliary indicator element and and TURA value geochemical anomaly map, and select and 3) identical projective parameter carries out projective transformation;

In uranium element geochemistry equal-value map, be that uranium element is abnormal by tired uranium element frequency at 25%～70% region labeling, obtain uranium element geochemical anomaly map;

In auxiliary indicator element geochemistry equal-value map, be that auxiliary element is abnormal by the region labeling of frequently tired auxiliary indicator element >=70%, obtain auxiliary element geochemical anomaly map;

In TURA value geochemistry equal-value map, be TURA value geochemical anomaly by the region labeling of TURA value≤3, obtain TURA value geochemical anomaly map;

7) abnormal morphology is judged:

In uranium element after above-mentioned projection, auxiliary indicator element and TURA value geochemical anomaly map, contrast digital geological map, retains and meets the abnormal of following characteristics, obtains uranium element after treatment, auxiliary indicator element, TURA value geochemical anomaly map;

1. abnormal morphology is planar or beading;

2. abnormal distributing position becomes favourable layer distribution region, ore deposit consistent with middle acid volcanic rock;

8) digital geological map of contrast Geological Prediction, in uranium element after treatment, auxiliary indicator element and TURA value geochemical anomaly map, by abnormal uranium element and TURA value geochemical anomaly and the abnormal superposition of more than one auxiliary indicator elements and be that one-level uranium becomes distant view target area, ore deposit with the region decision of the more than two kinds Beneficial Ore-forming key element coincidence of Geological Prediction;

It is that secondary uranium becomes distant view target area, ore deposit that one-level uranium is become to the abnormal region decision that becomes the TURA value geochemical anomaly superposition outside distant view target area, ore deposit with one-level uranium and overlap with a kind of Beneficial Ore-forming key element of Geological Prediction of uranium outside distant view target area, ore deposit;

Become distant view target area, ore deposit uranium element to be in addition extremely judged as three grades of uranium I and II uranium and become distant view target area, ore deposit.

2. a kind of volcanic type U-ore target selection method based on geochemical anomaly according to claim 1, is characterized in that: described section association analysis method is:

When there being known Volcanic Type Uranium Deposits, on the single element geochemistry equal-value map that known Volcanic Type Uranium Deposits point position is added to worked out, Linear profile is drawn in the position of passing through at known Volcanic Type Uranium Deposits, length profile is 1 km～10 km, carry out association analysis by the 50-90% degree of correlation, get three elements of degree of correlation maximum as auxiliary indicator element;

When there not being known Volcanic Type Uranium Deposits, on the single element geochemistry equal-value map that known volcanic type U-ore point and mineralization points point position is added to worked out, Linear profile is drawn in the position of passing through at known ore deposit point and mineralization points, length profile is 1 km～10 km, carry out association analysis by the 50-90% degree of correlation, get three elements of degree of correlation maximum as auxiliary indicator element;

When not having known Volcanic Type Uranium Deposits, ore deposit point and mineralization points, in selection molybdenum, silver, fluorine, beryllium, mercury, three elements are as auxiliary indicator element.