煌斑岩的分类、特征及成因  

Classification,characteristics and petrogenesis of lamprophyres:an overview

作　　者：刘秉翔 张招崇[1] 程志国[1] LIU Bingxiang;ZHANG Zhaochong;CHENG Zhiguo(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing,100083)

机构地区：[1]中国地质大学(北京)地质过程与矿产资源国家重点实验室,北京100083

出　　处：《地质学报》2021年第2期292-316,共25页Acta Geologica Sinica

基　　金：国家自然科学基金项目(编号41772057)资助成果。

摘　　要：作为最早被识别出的碱性岩石之一,煌斑岩因富含金和金刚石等矿产资源以及对理解深部地球动力学过程的重要作用而受到广泛重视,但是目前对于煌斑岩的成因还存在不同的认识。本文基于近年来对煌斑岩的研究成果,对它们的分类、特征以及岩石成因进行综述。根据国际地科联(IUGS)的分类标准,煌斑岩可以分为超镁铁质煌斑岩、钙碱性煌斑岩和碱性煌斑岩。研究发现,超镁铁质煌斑岩往往是伸展环境下岩浆作用的产物,与金伯利岩和碳酸岩有密切的成因关系;钙碱性煌斑岩通常发育在汇聚或被动大陆边缘环境,其岩石成因可能有多种机制(如基性岩浆的分异、岩浆混合以及交代富集地幔的部分熔融);碱性煌斑岩出露在离散型大陆边缘和板内构造环境,通常和碱性玄武质岩浆作用密切相关。不管岩石的形成环境和过程如何,超镁铁质煌斑岩、钙碱性煌斑岩和碱性煌斑岩被普遍认为是来自于经历了交代富集作用的地幔源区。最后,文章指出了煌斑岩研究过程中存在的一些科学问题,如富集的地幔源区存在的矿物相(金云母和角闪石)对产生钠质还是钾质岩浆的影响,控制岩浆在结晶过程中影响含水矿物斑晶形成的因素以及部分煌斑岩中碳酸岩球粒和钠长石的形成原因等。As some of the oldest recognized alkaline rocks,lamprophyres have been widely studied by geologists for hosting economic minerals such as gold,diamond.They are also significant in our understanding of the deep-mantle geodynamic processes.However,there are different understandings about the petrogenesis of lamprophyres.We summarized the research results of lamprophyres in recent decades as well as compiled a detailed overview of their classification,characteristics and petrogenesis in this paper.Lamprophyres can be divided into ultramafic lamprophyres,calc alkaline lamprophyres and alkaline lamprophyres according to the classification criteria from International Union of Geological Sciences(IUGS).Ultramafic lamprophyres are often the products of magmatism in an extension setting,which are associated with kimberlite and carbonatite.Calc-alkaline lamprophyres usually present in convergent and passive continental margin settings,and with several mechanisms of petrogenesis(e.g.differentiation of basic magma,magma mixing and low-degree partial melting of metasomatized mantle).Alkaline lamprophyres are usually closely related to alkaline basaltic magmatism from the divergent margins and intraplate tectonic settings.Regardless of the environmentand formation process of the rocks,these three types of lamprophyres are generally considered to be derived from a mantle source that has undergone metasomatic enrichment.Finally,we highlight some scientific problems in the study of lamprophyres,such as the influence of mineral phases(phlogopite and amphibole)in the enriched mantle source on the generation of sodic or potassic lamprophyric magma,the controlling factors in the formation of hydrous mineral phenocrysts,and the genesis of carbonate-rich"ocellar"texture and albite in the lamprophyres.

关 键 词：煌斑岩 分类 岩石学特征 岩石成因 地幔交代作用 

分 类 号：P588.15[天文地球—岩石学]