A new metallogenic model for the giant manganese deposits in northeastern Guizhou, China

Abstract

The recently discovered multiple world-class Nanhuanian manganese (Mn) ore deposits at Datangpo of northeastern Guizhou province in southern China provides substantial amount of Mn that can be economically important for industrial usage. Studies that we previously conducted suggest that these Mn ore deposits are likely manifestations of the deposition of volatile-rich Mn-bearing ore-forming materials originating from deep reservoirs. However, ore-forming structures that transport ore-forming materials, if existed, have not yet been identified. Here, integrated with three-dimensional (3D) geological modeling, aeromagnetic △T data processing and Bouguer gravity anomaly analysis, we found that the intersections of the northwest (NW)-trending early rift basins and the near east–west (EW)-trending Nanhua rift basins overlap with the localities of the giant Mn ore deposits in northeastern Guizhou. In addition, a seismic reflection profiles passing through the Mn mining district reveals an upward-widen, funnel-shaped seismically abnormal structure with a dimension of about 3-km-wide and 45-km-deep. The seismically abnormal structure highly likely represents a deep-seated diapir channel beneath the mining district. Such a structure could contribute to the transportation of Mn-bearing materials that are responsible for the final deposition of Mn ore deposits. This study not only offers a visualization of a deep-seated channel that may be part of ore-guiding structures, but also sheds light on a new metallogenic model of Mn ore deposit.