【摘要】 广西南丹-宜州台沟盆地是我国石炭系锰矿的重要富集区。根据构造和岩相古地理的演化特征,盆地内划分出3种台沟类型:南丹式台沟、龙头式台沟、里苗式台沟。早石炭世晚期存在两个成锰旋回,南丹-龙头地区为下旋回锰矿,同德-里苗地区为上旋回锰矿,反映了早石炭世晚期成锰中心由西北往东南迁移的过程。锰矿主要富集在区域性同沉积大断裂的转弯处、或与次级同沉积断裂的分支部位,距同沉积断裂200～1000m范围是锰矿最有利的富集部位(沉积中心)。根据同沉积断裂→台沟→岩相→锰矿的成矿规律,认为三岔-忻城同沉积断裂西侧的肯棚-洛富-里苗-塘岭地区的巴平组地层、天峨-东兰-九圩同沉积大断裂东北侧附近台沟盆地的榴江组及巴平组地层是今后深部锰矿的找矿方向。更多还原

【Abstract】 The Nandan-Yizhou platform-trench basin is an important enrichment area of Carboniferous manganese ores in China. According to the evolution characteristics of tectonics and lithofacies paleogeography,this paper divides the sedimentary facies of the basin into three types of platform trenches,named Nandan,Longtou and Limiao platform trench,respectively. There are two manganese precipitated cycles in these platform trenches,of which the lower cycle manganese deposit is in the Nandan-Longtou area and the upper cycle manganese deposit in the Tongde-Limiao area,reflecting the migration of manganese forming centers from northwest to southeast during the late Early Carboniferous. The manganese ore is mainly enriched at the bends of regional synsedimentary faults or branches of secondary synsedimentary faults,and the 200 ～ 1000 m range from these faults is the most favorable enrichment site( sedimentary center) of manganese deposits. Based on the metallogenic regularity of synsedimentary faults→platform trenches→lithofacies→manganese ore,it is considered that the prospecting targets of deep manganese deposits should be the strata of Baping Formation of the Kenpen-Luofu-Limiao-Tangling area on the west side of the Sancha-Xincheng synsedimentary fault and the strata of the Liujiang Formation and the Baping Formation in the platform-trench basin near the northeast side of the Tian’e-Donglan-Jiuxu synsedimentary fault.更多还原