矽卡岩作为湖南柿竹园矿集区的主要蚀变岩石类型，对该区成矿作用以及找矿勘探具有十分重要的作用。为此，对矽卡岩的岩石学、矿物学以及地球化学特征进行了系统研究。结果表明，该矿集区的矽卡岩以石榴子石矽卡岩为主，其次为硅灰石石榴子石矽卡岩、透闪石斜黝帘石矽卡岩，少量含白钨石榴子石矽卡岩、符山石石榴子石矽卡岩以及硅灰石矽卡岩等。矽卡岩通常具有粒状变晶结构、粒状片状变晶结构，且表现为块状构造、浸染状构造、网脉状构造、梳状构造以及条带状构造等。岩石主要由石榴子石、萤石、绿泥石、角闪石、绿帘石、透闪石、斜长石、黑云母、白云母、斜长石、石英、符山石以及方解石等组成。矽卡岩的主量成分主要包括 SiO2、Al2O3、Fe2O3、MgO 以及 CaO 等，微量以及稀土元素组成主要为 Li、Be、V、Co、Zn、Ga、Rb、Sr、Y、Ce、Nd、Pb 以及 Bi 等。轻、重稀土元素之间具有十分明显的分馏现象，且表现出南岭钨锡多金属矿床成矿花岗岩的典型特征。矽卡岩的主要原岩为沉积岩，包括灰岩、泥岩、泥质岩以及少量的泥质条带等，岩石成岩过程中主要受佘田桥组地层以及千里山花岗岩体的共同影响，且为强烈的还原环境。矽卡岩岩石产状与成矿作用和找矿预测密切联系，岩石形态突变部位常常更加有利于矿化富集。%Skarn is the main altered rock type and is of great importance to mineralization and ore-prospecting in the Shizhuyuan area of Hunan province, China. Its features of petrography, mineralogy and geochemistry were studied systematically. The results show that the skarn mainly consists of garnet skarn, secondary wollastonite-garnet skarn, tremolite-clinozoisite skarn, and few wolframine garnet skarn, idocrase-garnet skarn and wollastonite skarn with granoblastic texture, granular sheet crystalloblastic texture, and massive structure, disseminated structure, mesh-vein structure, comb structure, and banded structure. And, it is mainly composed of garnet, fluorite, chlorite, hornblende, epidote, tremolite, plagioclase, biotite, muscovite, plagioclase, quartz, idocrase, and calcite and so on. The chemical components mainly include SiO2, Al2O3, Fe2O3, MgO and CaO, and the trace elements and REEs consist of Li, Be, V, Co, Zn, Ga, Rb, Sr, Y, Ce, Nd, Pb and Bi, etc. And, the obvious fractionation exists between LREE and HREE, and it shows typical features of Nanling ore-forming granite for W−Sn polymetallic deposit. Skarn is derived from the sedimentary rock, such as limestone, mudstone, argillaceous rock, and few pelitic strips. It is affected by both Shetianqiao formation strata and Qianlishan granite during the diagenesis, indicating a strong reduction environment. The occurrence of skarn, whose mutation site is favorable to the mineralization enrichment, is closely related to the mineralization and prospecting.
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