华北陆块南缘熊耳期次火山岩地质地球化学特征  

Geological and Geochemical Features of the Middle Proterozoic Xiong'er Subvolcanic Rocks in the Southern Margin of the North China Block

作　　者：庞振山[1] 燕建设[2] 

机构地区：[1]中国地质大学,北京100083 [2]河南省地矿局,郑州450007

出　　处：《地质调查与研究》2004年第4期234-238,共5页Geological Survey and Research

基　　金：国土资源大调查项目 -豫西南地区铅锌银矿评价 (项目编号 :199910 2 0 0 2 2 7)

摘　　要：熊耳期次火山岩广泛分布于熊耳群火山岩及接近熊耳群底部的基底变质岩系中 ,活动时间贯穿整个熊耳期 ,以早期和晚期最为发育。次火山岩与围岩呈侵入接触 ,主要以岩脉 (墙 )、岩带、岩株、岩床等形态产出。岩石类型多样 ,包括超浅成 -浅成的基性、中性、酸性岩石。岩石地球化学研究表明 :次火山岩富FeO 、K2 O而贫CaO、MgO、Al2 O3 ,为钾质岩系 ,具岛弧型火山岩的地球化学 ,不同岩性的次火山岩是由同源岩浆结晶分异形成的。The Middle Proterozoic Xiong'er subvolcanic rocks are widely loucated in Xiong'er Group volcanic rocks and the metamorphic basement near the bottom of Xiong'er Group. They formed in the Xiong'er Period, and developed best during the early and late period. The subvolcanic rocks intruded in the country rocks. They mainly take the shapes of vein, dike, sill, stock etc. The rock types are varied, including hypabyssal-super hypabyssal basic, intermediate and acid rocks. The study on the geochemistry shows that the subvolcanic rocks are rich in FeO~*, K_2O, and poor in CaO, MgO, Al_2O_3. They belong to potassic rock system with the geo-features of the island arc volcanic rocks. The different subvolcanic rocks formed through the crystallization differentiation of the affinity magma.

关 键 词：熊耳期 次火山岩 地质地球化学特征 华北陆块南缘 

分 类 号：P594[天文地球—地球化学] .1[天文地球—地质学]