广东连平岑告高岭土矿地质特征及成因分析

Geological characteristics and genesis analysis of Cengao Kaolin deposit in Lianping,Guangdong

河源地区高岭土资源储量丰富,但大部分分布在东源县、紫金县、和平县等花岗岩岩体出露较多县份,且大部分以风化矿为主,形态以层状为主,而广东连平岑告高岭土矿矿床为脉状,赋存于沉积岩的断裂构造中。通过对其研究发现,其成因为花岗斑岩岩脉沿F_(2)断裂带充填,后经多期热液交代作用,发生钠长石、钾长石化热液蚀变,形成原生瓷石矿,为低温热液蚀变成因;地表的原生瓷石矿经后期风化淋滤形成风化砂质高岭土矿,为风化残积成因。2种矿石类型在空间上呈渐变过渡关系,其中原生瓷石矿矿化与花岗斑岩脉钠长石化、钾长石化呈正相关,风化砂质高岭土矿与原生瓷石矿的风化淋滤程度呈正相关。通过研究分析可知,沿花岗斑岩脉在地表的延伸方向有较好的高岭土找矿潜力。

Heyuan area is rich in Kaolin resources,but most of them are distributed in Dongyuan County,Zijin County,Heping County and other counties where granite bodies are exposed,and most of them are mainly weathered ores,mainly in layered form.The Cengao Kaolin deposit in Lianping,Guangdong,is vein shaped and occurs in the fault structure of sedimentary rocks.Through the study,it is found that the granite porphyry dyke was filled along the F_(2)fault zone,and then through multistage hydrothermal metasomatism,albite and K-feldspar hydrothermal alteration occurred,forming primary porcelain ore,which is of low-temperature hydrothermal alteration origin.The primary porcelain stone ore on the surface is weathered and leached to form weathered sandy Kaolin ore,which is of weathering residual origin.The two ore types show a gradual transition relationship in space,in which the mineralization of primary porcelain ore is positively related to albitization and K-feldsparization of granite porphyry vein,and the weathering leaching degree of weathered sandy kaolin ore is positively related to that of primary porcelain ore.