江西广昌头陂硅藻土矿床地质特征及成因  

Geological features and genesis of the diatomite ore deposit in Toupi of Guangchang County,Jiangxi Province

作　　者：杨华泽[1] 罗辉平 罗喜成[1] 李自敏 况沅忠 

机构地区：[1]江西省地质矿产勘查开发局赣西地质调查大队,江西南昌330030

出　　处：《地质学刊》2017年第4期573-581,共9页Journal of Geology

基　　金：江西省地质勘查基金项目“江西省宁都县百坑瓷石(瓷土)矿调查评价”(20163007)、“江西省广昌县山背硅藻土矿调查评价”(20170048)

摘　　要：基于矿床地质特征,初步分析了江西广昌头陂硅藻土矿床的成因,提出了下一步勘查方向。头陂硅藻土矿赋存于新近系头陂组上段,呈层状和似层状,平面上呈面型展布并延伸至矿段外。上部矿层以圆筛藻属硅藻为主,下部矿层以羽纹目硅藻为优势。新近纪以来,头陂淡水湖泊盆地在温暖、湿润气候条件下,硅藻快速繁殖生长;中新世中晚期以来,盆地外围大面积的铝硅酸盐岩化学风化作用和少量火山灰飘落于水体中为硅藻土形成提供物质条件;硅藻死亡后,其硅质骨骸则保存下来形成硅藻淤泥,经过初步成岩后,便形成了硅藻土层。头陂地区硅藻土矿找矿标志为新近纪新地层和水平层理发育的浅色沉积岩。Based on analyzing geological features of Toupi diatomite ore deposit, this paper discussed its genesis and put forward the next exploration direction. Located in the upper part of the Neogene Toupi Formation, this deposit is stratiform or stratoid, whose planar distribution extends beyond the ore section. The upper bedding is mainly diatom of Coscinodiscus, while the lower bedding is mainly pennales. Since the Tertiary, the freshwater lakes and basins have been rapidly growing in warm and humid climate, which results in rapid growth of diatomite. Since the Middle and Late Miocene, a large area of aluminosilicate weathered in the basin periphery and a small amount of volcanic ash have fallen into the water body, providing material conditions for the formation of diatomite. When diatom died, its bones were preserved and later turned into diatom mud. After the initial diagenesis, they formed a diatomite layer. The prospecting criteria of the Toupi diatomite deposit are light sedimentary rocks developed in the new strata and horizontal bedding of the Tertiary.

关 键 词：矿床地质特征 成因 头陂硅藻土矿 江西广昌 

分 类 号：P611.2[天文地球—矿床学] P619.265[天文地球—地质学]