1.2.1 Main research content

Based on remote sensing, geology, aerial radiography, gravity and magnetism, and DEM information processing and analysis, with the goal of in-depth mining and application of multi-source information, With the purpose of determining the further prospecting direction in the Xiangshan area, the following research work has been focused on:

Figure 1.1 Uranium ore distribution sketch in the Xiangshan ore field

1.2.1.1 Xiangshan Volcano - Research on the overall morphology of intrusive complexes

Mainly study their formation background, basement structure, morphological characteristics, relationship with regional stratigraphic structure and origin positioning mechanism. The study of the overall morphology of the Xiangshan volcanic-intrusive complex is the basis for the study of deep mineralization conditions.

1.2.1.2 Research on neotectonic movements

Through the image fusion and RGB synthesis of Landsat-7ETM+ multispectral data, the landforms, lithology, linear structures and rings in the Xiangshan area were compared. Conduct a comprehensive analysis of linear structures, focus on the Quaternary activity traces of linear structures, and explore the impact of neotectonic movements on the mineralization amplitude and deposit preservation in the area.

1.2.1.3 Comparative study of the northwest and southeast of Xiangshan

Xiangshan uranium deposits are mainly concentrated in the northwest, with few in the south and east. The author will conduct a comparative analysis of structural magma development characteristics, remote sensing images, gravity and magnetic performance, basement morphology, and mineralization characteristics to explore the main factors controlling the spatial distribution differences of Xiangshan uranium deposits.

1.2.1.4 Research on erosion and preservation status

Ore deposits are the historical product of geological processes and will undergo various changes and transformations after their formation. There are very few completely blind deposits in the Xiangshan ore field, and the deposits have suffered varying degrees of erosion. Although previous studies on the origin of mineral deposits have yielded fruitful results, research on the depth of erosion and preservation status of ore fields has been weak. Therefore, the author conducted an evaluation study on the depth of erosion or degree of erosion.

1.2.2 Research ideas

Guided by the theory of earth system science and based on the rich data, results and field surveys of previous generations, spatial database technology, information integration technology, Three-dimensional visualization technology, etc., were used to study the overall characteristics of the Xiangshan volcanic-intrusive complex and the preservation status of the deposits, providing a basis for in-depth prospecting in the Xiangshan ore field.

(1) Investigate and collect the development trends and technical data of remote sensing, geology, aerial radiography, gravity magnetic, and DEM technologies at home and abroad, and understand the current status and trends of the application of multi-source information integration technology in geological exploration, Clarify the key technologies, determine the research focus and the GIS technology platform used.

(2) Systematically collect data on regional geology, remote sensing, aerial radiography, aeromagnetic, surface geophysical and geochemical exploration and hydrogeology as well as related papers and monographs in the Xiangshan area. Understand the work level and research status of the study area, as well as existing problems in rock formation and mineralization.

(3) Digitize and image the collected materials and data, and construct a spatial database in Xiangshan area.

(4) With the support of spatial database technology and three-dimensional visualization technology, the multi-source information accumulated in the Xiangshan area is first analyzed one by one, and then the multi-source information is integrated. Through information mining, patterns are discovered, understanding is formed, and applied to exploration practice.

The technical roadmap is shown in Figure 1.2.

1.2.3 Research methods

Based on literature research, data collection, and establishment of spatial database, the following technical methods are mainly used:

(1) Field Geological surveys include surveys of topography, landforms, vegetation, and neotectonic movements, focusing on observing the activity patterns of main faults.

(2) Geology, ETM, aviation, gravity and magnetic, and DEM single information analysis. ETM image processing is carried out on the Erdas imagine8.6 platform. Through enhanced processing, ratio analysis, and principal component transformation, linear structures and alteration anomalies are extracted and geological analysis is performed; aerial information uses technical methods such as energy spectrum parameter calculation and image coding; heavy , magnetic information is processed by upward continuation and directional derivatives at different heights; DEM mainly uses methods such as terrain morphology analysis.

Figure 1.2 Technical Idea Block Diagram

(3) With the support of spatial database and other related technologies, remote sensing information is integrated with geological, aerial navigation, gravity and magnetic and DEM data. Conduct research on the overall characteristics and erosion state of the Xiangshan volcanic-intrusive complex and the ore preservation conditions. Information integration is the main technical method to be used in this study, including the integration of remote sensing and aviation radioactivity information, the integration of remote sensing and gravity and magnetic information, the integration of remote sensing and geochemical information, and the integration of remote sensing and geological and geographical information.

(4) Use the combination of C language and MATLAB software development platform to conduct three-dimensional visual analysis of geoscience data.

(5) Taking the in-depth excavation of basic geological information as the leading role, combined with other geoscientific information and integrated processing results, carry out comprehensive application research on key geological issues in the Xiangshan area.

The main innovation points of this topic are:

(1) Two shifts in research ideas are achieved, that is, from single information research to multi-source information research in the Xiangshan area. Research; from focusing on mineralization research to giving equal emphasis to mineralization and ore preservation research.

(2) In terms of research content, it focuses on the study of neotectonic movements and denudation states.

(3) In terms of research methods, it focuses on the comprehensive application of multi-source geoscience information. The combination of traditional geoscience research methods with spatial database technology and information integration technology is the main technical means of this study.