地质科技通报 (May 2022)
Comprehensive analysis of gravity and magnetic anomalies in Jinniu volcanic basin for prediction of ore deposits
Abstract
The middle and lower reaches of the Yangtze River is an important iron, copper, gold and other polymetallic metallogenic belt in China. The southern part of the Yangtze River is the southeast Hubei ore concentration area. As an important source of iron and copper deposits in China, several iron-rich copper deposits are concentrated in this area. The Jinniu volcanic basin is located in the southeastern Hubei ore concentration area. The basin has the ore potential of iron, copper, gold and other polymetallic deposits with the similar metallogenic conditions of other mining areas in this metallogenic belt. However, the basin has a thick overlying strata of magnetic rock and sedimentary rock, which increases the difficulty of ore prospecting. Therefore, it is necessary to strengthen the application of technologies for improving the effect of ore prediction. In the adjacent ore concentration areas, the prospecting work mainly focuses on gravity and magnetic data and combined with other geophysical data for comprehensive analysis, which lays a good foundation for the study of structural characteristics and the guidance of prospecting prediction. These previous works has proved that by comprehensive analysis and interpretation of high-precision gravity and magnetic data combined with other geophysical data, the tectonic framework characteristics, buried rocks and physical property distribution of the study area can be extracted, so as to infer the tectonic characteristics of the basin and its basement and put forward prospecting prediction. For the lack of systematic research and demand for prospecting in Jinniu volcanic basin, based on measured and collected geological and geophysical data, comprehensive analysis and interpretation of gravity and magnetic data combined with MT data were carried out. The techniques of linear signal extraction, multi-scale analysis, inversion and resistivity imaging, etc., were utilized to estimate the depth of the basin basement, delineate volcanic mechanism and buried rocks, and speculate fractures, basin boundary, and some areas of prospecting prospect. The such research has the guidance or reference significance for the basic geological survey and deep ore prediction in this area.
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