云南富宁地区晚三叠世基性侵入岩岩石学特征及其构造意义  

PETROLOGICAL CHARACTERISTICS AND TECTONIC SIGNIFICANCE OF LATE TRIASSIC BASIC INTRUSION IN FUNING AREA,YUNNAN

作　　者：刘陈明[1] 李序贵 田素梅 李小军 李维科 张坤 LIU Chen-ming;LI Xu-gui;TIAN Su-mei;LI Xiao-jun;LI Wei-ke;ZHANG Kun(Yunnan Professional Institute of Land Resources,Kunming 690093;Yunnan Geological Survey,Kunming 650216)

机构地区：[1]云南国土资源职业学院,云南昆明690093 [2]云南省地质调查院,云南昆明650216

出　　处：《云南地质》2022年第4期424-432,共9页Yunnan Geology

基　　金：中国地质调查局项目《云南1:5万那佐幅、里往幅、大普弄幅、花甲幅4幅区域地质调查》(编号:121201010000150008-09)。

摘　　要：通过对云南富宁地区厘定的一套基性侵入岩地质学、岩石学、地球化学分析。结果表明:该基性侵入岩主要由辉长辉绿岩、辉绿岩等组成,主要矿物由斜长石、辉石组成,局部可见微弱热液蚀变发育;SiO2含量43.92%~56.02%,全碱alk=3.12%~7.64%,具有富铝镁钙、低钛铁钾特点,属亚碱性系列;岩石呈现轻稀土富集、重稀土亏损的弱分异右倾式稀土元素配分模式特征,LREE/HREE=1.81~3.77,(La/Yb)N=4.33~11.89,(La/Lu)N=4.35~12.53,(Ce/Yb)N=5.43~49.87,(Gd/Yb)N=1.3~2.65,La/Sm=3.8~5.5,(La/Sm)N=2.07~3.46;微量元素表现为K、Sr、Nb、P、Zr、Ti存在不同程度富集、亏损,显示具同化混染作用岩浆特征;构造判别图显示出统一的板内构造背景,其时代可能为晚三叠世。According to the geological,petrological and geochemical analysis of a series of basic intrusion in Funing area,Yunnan,which mainly formed by gabbro-diabase,diabase,etc,mostly with mineral plagioclase and augite,locally showing weak hydrothermal alteration.SiO243.92%-56.02%,holo-alk 3.12%-7.64%,with characteristics of rich in Al,Mg,Ca,low Ti,Fe,K,belonging to subalkaline series,rock showing rich in LREE concentration,HREEdeficit weak differentiation right-dip REE distribution model,LREE/HREE 1.81-3.77,(La/Yb)N=4.33-11.89,(La/Lu)N=4.35-12.53,(Ce/Yb)N=5.43-49.87,(Gd/Yb)N=1.3-2.6,La/Sm=3.8-5.5,(La/Sm)N=2.07-3.46,trace element showing K,Sr,Nb,P,Z,Ti different degree concentration,deficit,showing mesitis contamination magma feature,tectonic discrimination diagram showing unified in-plate tectonic background,the age maybe Late Triassic.

关 键 词：晚三叠世侵入岩 辉长辉绿岩 岩石地球化学 构造背景 云南富宁 

分 类 号：P584[天文地球—岩石学] P595[天文地球—地质学]