Characteristics of Ore Bearing Rock in the Jinding Superlarge Lead-Zinc Mine, Lanping Basin, Western Yunnan

Key words: 
• Jinding lead-zinc mine /
• ore bearing rock /
• sedimentary characteristics /
• Lanping Basin

Abstract: There are two opposing views about the origin of the ore bearing rocks of the Jinding superlarge lead-zinc mine in Yunnan, Lanping:normal deposition and abnormal deposition. To determine the origin, firstly observation and description of the mining outcrop and drill cores in the mining area were carried out, based on geological mapping of the mining area, and secondly by analyzing the petrological characteristics, granularity and sedimentary facies of the ore bearing rock. It is believed that the ore bearing rock was deposited as a sublacustrine fan dominated by debris flows, identified both as a non-channel system of liquefied particle flow and as a channel system of sand debris flow with turbidity currents, and further subdivided into inner, middle and outer fan facies. The plane distribution of the sublacustrine fan shows that the grain size clearly changes from coarse to fine from east to west of the mining area. The lithology consists of thick-blocky limestone rock composed of breccia facies, gradually transitioning to cross-bedding in sandstone. The sand debris flow deposits have good reservoir properties and are also important ore bearing rocks with broad exploration prospects.