Paleoproterozoic skarn mineralization events and geodynamic background in the Jiao-Liao-Ji Belt: Geological, geochemical and chronological evidence from the Daqinggou Fe–Cu polymetallic deposit in Ji'an, NE China

•The Daqinggou Fe–Cu polymetallic deposit is a medium calcareous skarn-type Fe–Cu polymetallic deposit.•The ore-forming fluids and materials originated from the dimetasomatism of the microcline granite and calcareous carbonate rocks, and the diagenetic and metallogenic age was in the late Paleoproterozoic (∼1900 Ma).•The metallogenic environment was related to the late Paleoproterozoic arc-continent collision orogenic process in the JLJB.