钾玄质系列岩石的研究现状  

An Overview of Studies on Shoshonitic Rocks

作　　者：贾小辉[1,2] 王晓地[1,2] 杨文强[1] 牛志军[1] 

机构地区：[1]中国地质调查局武汉地质调查中心,武汉430223 [2]中国地质调查局花岗岩成岩成矿地质研究中心,武汉430223

出　　处：《地质论评》2017年第6期1587-1601,共15页Geological Review

基　　金：国家自然科学基金资助项目(编号:41302046);中国地质调查局基础地质研究项目(编号:12120113063600、DD20160064-01)的成果~~

摘　　要：钾玄质系列岩具有特殊的矿物学和地球化学特征,并具有重要的构造及成矿意义,自命名以来备受关注,但仍有许多问题存在较大争议,如岩石类型扩大化、是否存在壳源成因、板内环境如何判别等等。本文从以下几方面对钾玄质系列岩进行了系统总结:(1)作为一个独立的岩石系列,钾玄质系列岩仍缺失明确有效的岩石学、矿物学和地球化学等判别指标,相对统一的标准亟待建立;(2)与岛弧有关的钾玄质系列岩表现为高度富集大离子亲石元素和轻稀土元素,具有显著地TNT异常(Ta—Nb—Ti);大洋板内钾玄质系列岩具有典型的洋岛玄武岩(OIB)的微量元素特征;大陆板内钾玄质系列岩石兼具岛弧型和OIB型微量元素特征;(3)低硅钾玄质岩(SiO_2不大于63%)应当主要源于地幔源区,高硅钾玄质岩主要源于地壳源区,但更多情况下是二者的混合。Shoshonitic rocks have special characteristics of mineralogy and geochemistry, and important significance of geodynamic and mineralization.  Tremendous progress about shoshonitic rocks has been made in recent years, however, some topics on shoshonitic rocks are still disputable, such as, expansion of its definition, existence of crustal source and discrimination index of intraplate setting.  In this paper, we mainly introduce the current advances of the study on the shoshonitic rocks by data collecting and sorting. The main conlusions are followings： （1） As an independent rock series, it lacks unambiguous and effective discrimination indexes of petrology, mineralogy and geochemistry. Therefore, the relatively uniform standards need to be established urgently. （2） Shoshonitic rocks related to island arc are enriched in the large ion lithophile elements and light rare earth elements, with significant TNT abnormality. The shoshonitic rocks occurred in oceanic plate have typical characteristics of Ocean Island basalts, while those rocks related to continental intraplate have some features of Island Arc basalts or Ocean Island basalts. （3） Shoshonitic rocks with low and high silicon contents may be mainly derived from the mantle and crustal competent respectively. However, in most cases, they are origined from magma mixing.

关 键 词：钾玄质岩 地球化学 岩石成因 实验岩石学 

分 类 号：P588.14[天文地球—岩石学]