Research on remote sensing prospecting technology based on multi-source data fusion in deep-cutting areas

Abstract

Tectonically deep-cut areas are difficult to access due to the treacherous terrain, making it difficult to carry out fieldwork in these areas for geological prospecting. Liwu Copper-Zinc Mine is a medium-sized rich polymetallic deposit belonging to deep-cutting areas in tectonic structures. Complicated structures influence the ore development and formation in the region. With the introduction of remote sensing technology, geologic features and mineralisation abnormality information can be recognised effectively in such regions. This can provide scientific references for dividing potential metallogenic regions. Remote sensing images with sub-meter spatial resolutions were collected using the Worldview-2(WV-2) satellite to interpret mineralisation-related geologic bodies and analyse the distribution relationships of mineralisation-controlling structures. Multispectral near-infrared spectral information was acquired through the Landsat-8. Meanwhile, the alteration information of two hydrothermal solutions in the study area related to hydroxide radicals and iron staining was extracted via principal component analysis (PCA) based on Crosta technology. The alteration-related standard spectral information and the measured spectral information of known copper outcrops in the region were collected as guiding spectra. A comparative analysis between guiding spectra and GF-5 graphic information was conducted. Possible mineralisation information distributions in the study area were collected via a spectral angle mapper (SAM) and support vector machine (SVM). The results showed that the WV-2 images were able to accurately identify the mineralised geological bodies. The overall classification precisions of SAM- and SVM-based erratic rock mapping were 80.18% and 83.51%, respectively. The information on the hydroxyl iron staining anomaly had been well fitted to the actual alteration zone by field investigation. An analogy analysis between the multivariate remote sensing prospecting information collected by the above means and the existing typical mining areas in Liwu Region was conducted; the dense areas of mineral control structures and remote sensing anomalies were well integrated. The remote sensing metallogenic prediction model of the region was constructed on this basis. Meanwhile, the potential mineralisation was delineated at target zone 1. In conclusion, the presented technology is based on remote sensing data and the fusion of multi-resolutions. It can provide guidance and references for exploring potential metallogenic regions in deep-cutting areas, especially in fold-development regions.