河南栾川南部地区与Mo—W矿床有关的燕山期花岗岩特征

河南栾川南部分布着一系列与钼钨矿化有关的燕山期花岗岩小岩体。根据这些岩体的含矿性、地质及地球化学特征可将其分为三类。第一类岩体往往与大型一超大型Ｍｏ－Ｗ矿床有关，岩体顶部有纹层状石英层，石英辉钼矿脉发育。岩石中ＳｉＯ２、Ｋ２Ｏ、Ｒｂ含量高，Ｋ２Ｏ／Ｎａ２Ｏ、Ｒｂ／Ｓｒ比值高，Ａｌ２Ｏ３、ＦｅＯ、ＣａＯ、Ｎａ２Ｏ、Ｓｒ含量低。第二类岩体往往与中小型Ｍｏ－Ｗ矿床有关，岩体中含辉钼矿石英脉发育较差，岩石中ＳｉＯ２、Ｋ２Ｏ含量中等，Ｋ２Ｏ／Ｎａ２Ｏ比值中等。第三类岩体不含Ｍｏ－Ｗ矿，岩体中各种脉体不发育，岩石中ＳｉＯ２、Ｋ２Ｏ、Ｒｂ含量低，Ｋ２Ｏ／Ｎａ２Ｏ、Ｒｂ／Ｓｒ比值相对较低，Ａｌ２Ｏ３、Ｎａ２Ｏ、Ｓｒ含量相对较高。研究还表明小岩体的分异演化程度与小岩体的合矿性有密切的内在联系。

Characteristics of Yanshanian Granites Related toMolybdenum-Tungsten Deposits in the SouthernPart of Luanchuan County, Henan Province

There are lots of Yanshanian granitoid stocks related to molybdenum-tungsten mineralization distributed in the southern part of Luanchuan County, Henan Province. According to their mineralizationintensity, geological and geochemical characteristics, these stocks can be divided into three groups. The firstgroup of rocks, with relatively high SiO2, K2O, Rb contents and K2O/Na2O, Rb/Sr ratios as well as relativelylow Al2O3, FeO, CaO, Na2O, Sr contents, are associated with super-large size W-Mo ore deposits and has welldeveloped molybdenite-quartz veins. In the upper part of these stocks the crenulate quartz layers occur. The second group of rocks, with medium SiO2, K2O contents and K2O/Na2O ratios, are related to some medium orsmall W-Mo deposits and molybdenite-quartz veins are less developed. The third group of rocks, with low SiO2,K2O, Rb contents and K2O/Na2O, Rb/Sr ratios as well as relatively high Al2O3, Na2O, Sr contents, are almostbarren and quartz-veins are least developed. Investigation shows that the magma-differentiation and evolutiondegree of the stocks have close relation to mineralization intensity.