高镁安山岩及其地球动力学意义  

High-Mg andesites and their geodynamic implications

作　　者：唐功建[1,2] 王强[1] 

机构地区：[1]中国科学院广州地球化学研究所同位素年代学与地球化学重点实验室,广州510640 [2]中国科学院研究生院,北京100039

出　　处：《岩石学报》2010年第8期2495-2512,共18页Acta Petrologica Sinica

基　　金：中国科学院创新项目(KZCX1-YW-15-2、KZCX2-YW-128);国家重点基础研究发展规划项目(2007CB411308、2009CB421004);国家自然科学基金项目(40721063)联合资助

摘　　要：高镁安山岩是当前国际地质研究的一个热点之一。本文重点介绍了高镁安山岩的分类、成因、成矿和地球动力学意义。高镁安山岩主要包括高镁埃达克岩、巴哈岩、赞岐岩和玻安岩等四类。高镁安山岩的成分复杂,可以包含地幔源区组分,以及俯冲大洋板片(玄武质洋壳或洋壳沉积物)或俯冲陆壳沉积物熔体或流体组分,有时也可能包含拆沉下地壳熔体组分。高镁安山岩可以通过地幔橄榄岩的直接熔融形成,也可通过熔体与地幔的相互作用形成。高镁安山岩的形成环境特殊:除青藏高原中部的一些新生代高镁安山岩外,几乎所有其它新生代的高镁安山岩都形成在会聚板块边界,且大都与年轻的、热的洋壳或洋脊的俯冲有关。高镁安山岩对揭示大陆地壳的形成以及金属矿化方面都有非常重要的意义。最后,对当前高镁安山岩的研究中存在的问题进行了探讨。High-Mg andesites ( HMAs) have recently been one of focuses on the international geological research. In this paper,we mainly introduce the classification,petrogenesis,metallogeny and geodynamic implications of the HMAs. The HMAs can be classified as adakitic,bajaitic,sanukitic and boninitic sub-types. The HMAs may contain mantle-derived component,and subducted oceanic slab ( basaltic oceanic crust or sediments) or subducted sediment-dominated continental crust-derived melts ( or fluid) ,or sometimes delaminated lower crust-derived melts. The HMAs may be directly generated by partial melting of mantle peridotite or the interaction between melts and mantle peridotites. The geological setting for the HMAs is very special. Except the Cenozoic HMAs in the central Tibet plateau,nearly all other Cenozoic HMAs occur along the boundaries between convergent plates,and their petrogenesis is mainly related to the subdution of young and hot oceanic crust or oceanic ridges. The HMAs provides key insights into the continental crustal growth and metal mineralization. Some problems regarding the present research on the HMAs are discussed at last.

关 键 词：高镁安山岩 板片熔体(或流体) 俯冲沉积物 交代作用 岛弧岩浆作用 

分 类 号：P588.144[天文地球—岩石学]