摘要
滇东地区的富磷矿床,系风化富集形成,原生含矿层为下寒武统梅树村组。富集成矿的内在因素主要是原生含矿层的岩相、岩性、含磷丰度,区内的含磷层均为白云质磷块岩;外在因素首先是具备地表渗流水和地下环流水的储集、渗透、运移的条件,风化富集深度限于地下潜水面以上。富磷矿床处于地形平缓区,多系顺向坡,岩层倾斜平缓,盖层为白云岩或石英砂岩,其厚度一般小于30米。判别本区风化富集磷矿的定量指标主要依据化学组分及其相关比值。笔者采用碳酸盐(特别是CO_2)含量来标定磷矿石的风化强度。风化磷矿石经简易的工艺流程(擦洗脱泥)即可获得优质精矿。磷矿风化矿的勘查方法有其独特性,研究矿床本身的同时要研究其富集的自然地理因素,地表与深部地质研究并重。
Massive phosphorus-rich deposits in E Yunnan were formed by weathering enrichment, their primary ore-bearing beds belong to the Meishucun Formation of Lower Cambrian. The internal factors forming these deposits are mainly the lithofacies, lithologies and phosphoric abundance of the primary orebearing beds. The primary ore beds of the weathering enriched phosphorus ores with middle—, and large-scales which have been ascertained are all the dolomitic phosphorite. The external factors of the first importance for minera-lization require a hydrogeologic condition promoting the reservoir, permeation and migration of the sueface filtration and underground circulation water. The depths of weathering enrichment were restricted above the water table. The gentle topography, gentle occurrence of primary rock and consequent slope are found in mining areas, and the covering strata consist of the dolomitite or quartz sandstone with a thickness of less than 30 m. The quantitative indexes discriminating the weathering enriched phosphorus ores in E Yunnan are mostly based on the chemical components and their relative ratioes. The authors use the carbonate content(esp. the CO_2 content)to demarcate the weathering intensity of phosphorus ores. Changes in MgO, CO_2/P_2O_5, CO_2+MgO/P_2 O_5 and CaO/P_2O_5 show approximate or consistent tendency with the CO_2 content. The phosphorus concentrates of high quality can be obtained from weathering phosphorus ores through easy and ripe process flow——cleaning desliming. Because of the exploratory methods for the weathering phosphorus deposits having its own uniqueness, men should pay equal attention to understanding both of the deposit itself and its natural geographic factors for enrichment, and understanding both of the surface and deep part in deposit during exploration.
出处
《云南地质》
1990年第3期165-185,共21页
Yunnan Geology
