Geological and mineral resources survey as well as magmatism and mineralization in Dayana area of Dong Ujimqin Banner, Inner Mongolia

1:50000 geological and mineral survey shows that the main strata in Dayana area of Dong Ujimqin Banner in Inner Mongolia are the Early Devonian Niqiuhe Formation and the Late Carboniferous-Early Permian Gegenaobo Formation, followed by the Late Jurassic, Neogene and Quaternary strata. The Niqiuhe Formation is composed of shallow marine sediments, formed on the passive continental margin. The Gegenaobao Formation is related to the subduction of the Siberian plate. The structure of the study area is mainly composed of NE-striking fold structure. The faults in the study area occur in different groups, and the ore-controlling fault is mainly NE-and nearly NS-striking faults. There are two periods of magmatic intrusion and associated polymetallic mineralization in the study area. The formation of polymetallic deposits is characterized by various types, long mineralization time span and diverse tectonic settings. The ore deposits include hydrothermal-filled lead-zinc-silver polymetallic deposits, tectonic alteration rock type gold deposits, and high-medium-temperature hydrothermal tungsten-molybdenum deposits (wolframite-bearing quartz vein type). These deposits were formed in continental-arc magmatism caused by subduction of oceanic plate, continental-continental collision and post-orogenic stretched collapse background, respectively. The long-term tectonic-magmatism in the study area provides good geological conditions for mineralization, and hence the area has a good prospecting potential for polymetallic deposits.