通过对矽卡岩岩石学特征、矿物学特征研究,发现矽卡岩主要产于大理岩和石英闪长岩、花岗斑岩接触带上,垂向上多有大理岩-硅化角岩-矽卡岩化大理岩-硅灰石矽卡岩-透辉石矽卡岩-石榴子石矽卡岩-石英闪长岩的分带特征.矽卡岩岩石地球化学特征、稀土元素和微量元素特征显示矽卡岩主要为钙矽卡岩,具有弱Eu负异常和轻稀土富集等特征；同时具有富集Rb、Th、Cs、U等大离子亲石元素和亏损Hf、Ti、Y等高场强元素特征.矽卡岩地球化学特征受大理岩和石英闪长岩、花岗斑岩的控制和影响,显示其与大理岩、石英闪长岩和花岗斑岩成因上有密切关系.通过对班公湖-怒江成矿带成矿背景和时空关系的讨论,指示了尕尔穷矿床成因是与岩浆热液有关的接触交代型矿床.%The petrologic and mineralogical characteristics of the skarn in the Gaerqiong copper-gold deposit were studied in this paper. The skarn is mainly distributed in the contact zone between marble and quartz diorite as well as granite porphyry. It is distributed vertically as the zoning of marble-silicified hornfels-skarnized marble-wollastonite skarn-diopside skarn-garnet skarn-quartz diorite. A study of petrochemical, rare earth and trace element characteristics of the skarn-type ore shows that the skarn is calcic skarn, which has characteristics of weak negative Eu anomalies and LREE enrichment as well as the enrichment of large ion lithophile elements such as Rb, Th, Cs and U and the depletion of high field strength elements such as Hf, Ti and Y. The geochemical characteristics of skarn are controlled and affected by marbles, quartz diorite and granite porphyry. It is held that the skarn is genetically closely related to marble, quartz diorite and granite porphyry. Based on a discussion on the rnformation background of the Bangonghu-Nujiang metallogenic belt and the temporal-spatial relationship, the authors consider that the Gaerqiong deposit is a magmatic hydrothermal contact metasomatic type ore deposit.
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