Application of high-resolution remote sensing technology for the iron ore deposits of the West Kunlun Mountains in China

Abstract

This study focuses on the iron ore of Taxkorgan and Heiqia in the West Kunlun mountains as a case study, for the application of WorldView−2 and IKONOS remote sensing images as major data sources in the fabrication of a standard image map and in the adoption of image enhancement methods to extract information on the ore-controlling factors and mineralization, to interpret remote sensing for the mineral resources in these areas. ASTER, WorldView−2, and IKONOS data were applied for the extraction of alteration anomaly information. With an appropriate amount of field sampling and verification tests, this was used to establish a remote sensing geology prospecting model, that would provide the basis for future remote sensing of metalloge nic belts in West Kunlun in the hope of discovering similar minerals. Survey results showed four additional iron ore mineralization belts could be delineated in the Taxkorgan area. A comparative analysis conducted for part of the field confirmation and the known mineral deposits indicated good reliability. In Heiqia, a siderite-haematite mineralization zone was observed with copperlead-zinc formation, 60-km in length and 200–500 m wide, which includes several mineralized bodies. The ore bodies, appear as stratoid, lenticular, or podiform morphologies and were located in the transition site from clastic to carbonate rocks of the D segment in the Wenquangou Group. The ore bodies generally occur within 40°–50° strike and 68°–81° dip, in accordance to the strata. The length of the single body varies from several hundred metres to more than 9500 m. Its exposed thickness on the surface ranges from 2–50 m, and the general thickness was approximately 15 m. The surface ore minerals were mainly haematite and limonite, with a small amount of siderite. Therefore, high-resolution remote sensing technology is suitable for iron ore geological and mineral remote sensing surveying. It is advantageous in both high-ground resolution of optical characteristics and a certain spectral recognition capability, and is effective not only for information extraction from a large area, but also for recognition of local mineralization outcrops. Therefore, high-resolution remote sensing technology is valuable for popularization. an effective, prospective means of acquiring the geological anoma ly information related closely to ore-bearing strata, mineralized alteration zones, contact metamorphic zones, and tectonic zones (SHANG, 2009; WANG et al., 2011; CHEN et al., 2012; JIN et al., 2014; ZHANG et al., 2015; YANG & ZHAO, 2015; HOWARI et al., 2019; FAN et al., 2021). Located at the junction of the Palaeo–Asian and Tethyan tectonic domains, West Kunlun is an important part of the Qin–Qi– Kun tectonic belt of China, and also serves as an important area for studying the evolution of the Tethyan Ocean (PAN,1989, 1994, 1999; JIANG & ZHU, 1992; CHENG, 1994; JIANG & ZHU, 1992, 2002; YANG, 1994; PAN et al., 1995; PAN et al., 1996; CUI et al., 2006; WU et al., 2008; WANG et al., 2013; LI et al, 2011. LI, 2015; MENG et al., 2019). West Kunlun is characterized by strata exposed from Palaeoproterozoic to Mesozoic age (WANG H et al., 2016; ZHAO et al., 2010), by strong folds and faults (WU et al., 2008), and by the experience of multistage and various types of tectonic events (LU et al., 2003; YANG et al., 2004; XU et al., 2004; LI et al., 2008), or geological events in different periods that are superimposed on each other, such as multistage magmatism and multistage metamorphism with complex magArticle history: Manuscript received May 09, 2019 Revised manuscript accepted February 03, 2021 Available online February 28, 2021