布谷马西钾盐矿区卜育矿段盐系地层沉积旋回划分  

Division of sedimentary cycles of the salt strata in Buyu ore block of Mboukoumassi sylvite mining area

作　　者：栾元滇 田宁 刘东义 岳伟佳 王宏伟 Luan Yuandian;Tian Ning;Liu Dongyi;Yue Weijia;Wang Hongwei(Hebei Shandong Provincial Geo-mineral Engineering Exploration Institute,Jinan,Shandong,250014,China)

机构地区：[1]山东省地矿工程勘察院,山东济南250014

出　　处：《化工矿产地质》2020年第3期225-230,共6页Geology of Chemical Minerals

摘　　要：布谷马西钾盐矿区卜育矿段位于加蓬-安哥拉滨海盆地之下刚果盆地中部,地表覆第四系松散沉积,下伏新近系、白垩系、元古界。白垩系中部盐系地层是钾盐矿的赋矿层位,于该层位已发现多处钾盐矿床。该区盐系地层为光卤石岩和石盐岩互层韵律沉积,其间发育连续分布的沥青页岩7层,溢晶石岩2层。以沥青页岩和溢晶石岩为标志,将该区盐系地层划分为7个沉积旋回,每一旋回代表一次大的沉积事件。每一旋回的沉积特征不同,反映其沉积环境有差异。Ⅰ、Ⅱ旋回分布连续,光卤石岩层较厚,为光卤石型钾盐矿的成矿有利部位。Ⅵ、Ⅶ旋回由北向南渐趋变厚,旋回上部经淋滤,发育含钾石盐石盐岩,为钾石盐型钾盐矿成矿有利部位。Buyu ore block of Mboukoumassi sylvite mining area is located in the central Congo basin which belongs to the Gabon-Angola coastal basin, this basin is covered with loose quaternary sediments on the surface, underlying neozoic, Cretaceous and Proterozoic strata. The middle salt strata of the Cretaceous strata are the ore-bearing strata of the potassium salt deposits, in which a number of potash salt deposits have been found. The salt strata in this area are interbedded rhythmic deposition of carnallite and halite, among which 7 layers of bituminous shale and 2 layers of tachydrite are developed continuously. Marked by bituminous shale and tachydrite, the salt strata in this area are divided into seven sedimentary cycles, each of which represents a major sedimentary event. The sedimentary characteristics of each cycle are different, which reflects the difference of sedimentary environment. Continuous distribution of Ⅰ、Ⅱ cycles and thick carnallite strata are favorable sites for the mineralization of carnallite-type potassium salt deposits. From north to south, the Ⅵ、Ⅶ cycle gradually became thicker, and the upper part of the cycle was leached to develop potassium salt rock, which is a favorable part in the mineralization of potassium salt type.

关 键 词：布谷马西钾盐矿区 卜育矿段 盐系地层 沉积旋回 

分 类 号：P619.211[天文地球—矿床学]