滇东磷块岩矿床中磷灰石的富集特征

THE ENRICHMENT CHARACTERISTICS OF APATITE FROM PHOSPHORITES IN EAST YUNNAN

本文重点对滇东地区原生磷块岩和风化富集磷块岩中磷灰石特征进行对比研究，总结磷灰石富集规律。首先按风化程度、矿石组分结构构造不同特点，将磷块岩划分为十种矿石自然类型。通过对不同成因类型磷灰石的化学成分分析、微量元素分析、拉曼光谱、ＥＰＲ光谱、微形态和微组构研究，根据ＣＯ，ＯＨ￣－，Ｆ￣－的含量变化，将本区磷灰石划分为四个亚种，首次总结出磷灰石不同亚种与磷块岩类型之间成因内在联系。提出氟磷灰石主要形成于风化磷块岩中，碳氟磷灰石主要形成于原生沉积磷块岩中，羟碳氟磷灰石是组成原生菌藻磷块岩主要矿物的新认识。磷灰石的富集受内外因素的控制，滇池周边原生沉积磷块岩主要以碳酸盐类磷块岩为主，这种化学活性强的矿层为本区风化富集磷矿提供了极好的物质基础，再加上该区有利的气候、地形地貌、断裂构造及水文地质条件等，形成了优质风化磷矿。

This present paper deals with typomorphic characteristics of apatite in primary and weathered phosphorite,and with en richment rule of apatite.The phosphorite in the study area was first divided into ten main ore types affiliated to two groups of primary and weathered phos-phorite.The relationship between chemical composition analysis,trace element analysis,Raman spec-trum,EPR spectrum,microtopographic and microstructural analysis for different genetic apatites is investigated, According to the variation of,F￣-and OH￣-contents the apatite is classified into four subspecies and their genetic correlation is recognized. It shows that fluorapatite were mainly formcd in weathered phosphorite,earbonate fluorapatite were mainly formed in primary sedimentary phosphorite and hydroxyl-carbonate apatite were main mineral of primary algae-bac-terial phosphorite.The enriched apatite were formed under the control of internal and external factors,sllch as primary ore(dolomitic grain-phosphorite),climate,topography,tectonic and hydrologic factors.