塔里木地台南缘发现钾镁煌斑岩

首次在塔里木地台南缘皮山县境内找到钾镁煌斑岩，它们呈脉状产出，围岩为白云母石英片岩。该钾镁煌斑岩的岩石化学成分与亚洲钾镁煌斑岩的平均岩石化学成分接近，与澳大利亚西金伯利地区钾镁煌斑岩一致，稀土元素及其配分模式位于世界钾镁煌斑岩的范围之内，其中大多数标本具有已知世界钾镁煌斑岩的共同微量元素特征：具Ｂａ、Ｋ、Ｌａ和Ｃｅ的正异常及Ｔａ、Ｎｂ、Ｓｒ和Ｔｉ的负异常。该钾镁煌斑岩的发现对研究区金刚石找矿和深部地质过程研究均具深远意义。

DISCOVERY OF LAMPROITE IN SOUTH MARGIN OF TARIM PLATFORM, CHINA

It is the first time that lamproites are found in south margin of the Tarim Platform. They occure as dykes. Their wall rocks are muscovite quartz schist. Chemical compositions of the lamproites are very close to the average composition of Asia lamproites and coincide with those of the west Kimberley lamproites, Australia. Their REE compositions and patterns lie within the area of world lamproites. Most lamproite samples we found exist the common characteristics of lamproites: with positive anomaly in Ba K La and Ce and negative anomaly in Ta Nb Sr and Ti. The discovery of lamproites in this area is of farreaching significance in diamond prospecting and in research on deep geological process of the Tarim Platform.