赣东北港边火成杂岩体岩浆混合作用结构类型与成因机理  

TEXTURE TYPES AND GENETIC MECHANISM OF MAGMA MIXING IN GANGBIAN MAGMA-MIXED COMPLEX AND MAFIC ENCLAVES FROM NORTHEASTERN JIANGXI PROVINCE

作　　者：周勇[1] 李昌年[1] 钟称生[1] 毕金龙[2] 

机构地区：[1]中国地质大学地球科学学院,湖北武汉430074 [2]中国地质大学地质过程与矿产资源重点实验室,湖北武汉430074

出　　处：《矿物学报》2006年第2期181-188,共8页Acta Mineralogica Sinica

基　　金：国家自然科学基金项目(批准号:40172024)

摘　　要：赣东北前寒武纪港边火成杂岩体广泛发育不同类型的矿物间不平衡结构,指示该杂岩体曾发生过广泛的岩浆混合作用。对该杂岩体进行详细的薄片岩石学研究,总结了岩浆混合结构类型,包括斜长石环边、角闪石环带、文象钾长石的环斑结构与斜长石反环斑结构、石英-角闪石眼球状、钾长石巨斑的角闪石环和蜂窝状的斜长石等混合结构类型;镁铁质包体中指示岩浆混合作用的结构类型:石英/钾长石嵌晶结构、榍石-长石眼球结构、叶片状黑云母、针状磷灰石结构、斜长石的细条状结构、斜长石的蜂窝状环和斜长石的海绵式蜂窝状熔融结构,对这些结构类型进行了成因机理讨论。There are various lopsided texture types among minerals, indicating extensive magma mixing in the Precambrian Gangbian magma-mixed complex from northeastern Jiangxi Province. On the basis of observations of thin sections of rocks in the Gangbian complex body, this paper summarizes magma-mixed textures, including plagioclase rim, zones in hornblende, rapakivi texture of graphic K-feldspar, antirapakivi texture of plagioclase, quartz-hornblende ocellar, hornblende zones in K-feldspar phenocrysts and boxy celhdar plagioclase. Some textures in mafic enclaves of other complex bodies including poikilitic quartz/k-feldspar, sphene cellar, blade biotite, acicular apatite, small plagioclase laths, spike zones in plagioclase and spongy cellular plagioclase, which indicate magma mixing but cannot be found in the Gangbian complex body, are also introduced in this paper. These textures come into being when hot mafic magma found its way into felsic magma, or felsic magma into hot mafic magma. By analyzing these textures, this paper explains the genetic mechanism and probes into the magma-mixing mode and process of the complex.

关 键 词：港边火成杂岩体 岩浆混合作用 结构类型 成因机理 

分 类 号：P583[天文地球—岩石学] P588.12[天文地球—地质学]