鄂北风化斑状花岗岩型钾长石矿床工业指标探究

Industrial Index of Weathered Porphyritic Granite Type Potassium Feldspar Deposit in Northern Hubei Province

鄂北地区产出丰富的风化斑状花岗岩型钾长石矿,但缺乏专门的地质勘查规范和明确的工业指标,给该类钾长石矿的勘查开发和管理带来不便。以七尖峰岩体北部的上大南冲钾长石矿床为例,通过系统布置小竖井坑探和钻探工程,采集钾长石化学分析样品和含矿率样品,探究风化斑状花岗岩型钾长石矿床的工业指标。综合该矿床样品的统计数据和区内矿山开采的实际情况,拟定了该矿床的工业指标,即矿石有用矿物:粒径≥1 cm的钾长石斑晶;矿石有用矿物的化学成分:K_(2)O+Na_(2)O含量≥11.0%、K_(2)O/Na_(2)O比值≥2.0、Fe_(2)O_(3)含量≤2.5%;矿石有用矿物的含矿率:单工程平均≥25%。研究成果可为鄂北乃至其他地区的风化斑状花岗岩型钾长石矿床的勘查开发提供借鉴,建议及时建立该类矿床勘查的地方标准,促进钾长石矿的规范管理。

There are abundant weathered porphyritic granite type potassium feldspar deposits in northern Hubei Province,but there is a lack of special geological exploration specifications and clear industrial indicators,which brings inconvenience to the exploration,development and management of such potassium feldspar deposits.Taking the Shangdananchong porphyritic granite deposit in the north of Qijianfeng rock mass as an example,through the systematic arrangement of small shaft and drilling engineering,the chemical analysis samples and ore-bearing rate samples of potassium feldspar were collected to explore the industrial indicators of weathered porphyritic granite type potassium feldspar deposits.Based on the statistical data of the samples of the deposit and the actual situation of mining in the area,the industrial indicators of the deposit is drawn up,that is,the useful minerals of the ore:potassium feldspar phenocrysts with particle size≥1 cm;the chemical composition of ore useful minerals:K_(2) O+Na_(2) O content≥11.0%,K_(2) O/Na_(2) O ratio≥2.0,Fe_(2) O_(3) content≤2.5%;the ore-bearing rate of useful minerals in ore:single project average≥25%.The research results can provide reference for the exploration and development of weathered porphyritic granite type potassium feldspar deposits in northern Hubei and other regions.It is suggested that local standards for such deposits should be established in time to promote the standardized management of potassium feldspar deposits.