The Galinge skarn iron polymetallic ore deposit of western Qinghai Province lies in central Qimantag metal-logenic belt. Ore bodies are 'seated in the contact zone between granodiorites, adamellite and dolomitic marble and in the marble and altered andesites which are distributed along the NWW-striking rupture structural fracture zone in the exocontact zone. From the invading contact zone to the east, the zonation of skarn minerals is obvious and can be mainly divided into three ore-bearing skarn zones: magnesian skarn zone with Fe, calcium skarn zone with Fe and Cu and manganoan-calcium skarn zone with Fe, Pb and Zn. The main skarn minerals in thernmagnesian skarn zone include forsterite and its altered serpentine, chondrodite, diopsite and chinochlorite, and the main metal mineral is magnetite; the calcium skarn is composed of hastingsite, ferroactinolite, hedenbergite, delessite, apatite and andesine, and the associated metal minerals are magnetite, pyrrhotite and a little chalcopy-rite; the skarn minerals related to the manganoan-calcium skarn zone are manganhedenbergite, andradite, grossular, brunsvigite, epidote, wollastonite, apatite and anorthite, and the metal minerals are composed of galena, sphalerite, magnetite and pyrrhotite. Based on mineral assemblages, the authors divide the metallogenic periods into skarn period, hydrothermal period and sulfide period. Different periods have different stages: the skarn period is divided into early and late stage. The main chemical composition of early stages of skarn period is grossular (Gro67~99) and diopsite (Di96~98); The main chemical composition of the late stage of skarn is andradite (Ad78~98) and hedenbergite (Hd68-84). Through a comparison with the deposits in eastern China, the authors have found that manganoan-calcium skarn zone is a transitional type to the manganoan skarn zone, and it has the guiding significance in search for mineralization type related to the manganoan skarn.%尕林格矽卡岩型铁多金属矿床位于青海省西部祁曼塔格成矿亚带的中部.矿体处于花岗闪长岩与滩间山群白云质大理岩接触带内以及外接触带沿NWW向断裂构造破碎带分布的大理岩和蚀变安山岩内.从侵入接触带往东,蚀变岩石分带性明显,主要划分出3种含矿矽卡岩带:含Fe的镁质矽卡岩带,含Fe、Cu的钙质矽卡岩带,含Fe、Pb、Zn的锰-钙质矽卡岩带.镁质矽卡岩带的矽卡岩矿物主要包括镁橄榄石及其蚀变矿物蛇纹石、粒硅镁石、透辉石、斜绿泥石,有关的金属矿物主要为磁铁矿.钙质矽卡岩带的主要矽卡岩矿物有绿钙闪石、铁阳起石、钙铁辉石、铁叶绿泥石、磷灰石、中长石,有关的金属矿物为磁铁矿、磁黄铁矿和少量黄铜矿.与锰-钙质矽卡岩有关的矽卡岩矿物有锰钙铁辉石、钙铁榴石、钙铝榴石、铁镁绿泥石、绿帘石、硅灰石、磷灰石、钙长石等,金属矿物有方铅矿、闪锌矿、磁铁矿和磁黄铁矿.通过对矿物组合的研究,确定了不同矿物组合的生成关系,划分了成矿期次,分为矽卡岩期、退化蚀变期和金属硫化物期,矽卡岩期又分为早、晚2个阶段.矽卡岩早期生成的石榴子石的化学成分端员以钙铝榴石(Gro67～ 99)为主,辉石的成分端员以透辉石(Di96～ 98)为主；矽卡岩期晚期阶段石榴子石的化学成分端员以钙铁榴石(Ad78～98)为主,辉石的成分端员以钙铁辉石(Hd68～ 84)为主.与中国东部矽卡岩型矿床进行对比后发现,锰-钙质矽卡岩带是一种向锰质矽卡岩带过渡的类型,对于寻找与锰质矽卡岩有关的矿化类型具有指示意义.
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