钾霞橄黄长岩的研究进展  

Progress in the Study of Kamafugites

作　　者：张金博 徐梦婧 吴彦旺 赵佩云 肖雪 ZHANG Jinbo;XU Mengjing;WU Yanwang;ZHAO Peiyun;XIAO Xue(School of Geology and Geomatics,TCU,Tianjin 300384,China)

机构地区：[1]天津城建大学地质与测绘学院,天津300384

出　　处：《天津城建大学学报》2022年第2期92-98,104,共8页Journal of Tianjin Chengjian University

基　　金：国家自然科学基金(41503022,41772215);天津城建大学科研启动项目(5147203)。

摘　　要：钾霞橄黄长岩是一种贫SiO_(2)和Al_(2)O_(3),富碱的超基性超钾质火山岩,是了解地幔的重要窗口.本文总结了国内外钾霞橄黄长岩已有的研究成果,在此基础上对比分析了不同地区钾霞橄黄长岩的岩石学、全岩地球化学和同位素等特征.研究结果显示,钾霞橄黄长岩主要由橄榄石、金云母、白榴石、钾长石和辉石类矿物组成.钾霞橄黄长岩富集不相容元素,显示了富集地幔特征,但意大利钾霞橄黄长岩明显亏损Nb、Ta、Zr、Hf等高场强元素,而中国钾霞橄黄长岩则具有亏损地幔的同位素特征.通过地球化学分析,目前普遍认为钾霞橄黄长岩形成于伸展环境,可能形成于同造山的后碰撞阶段,或与地幔柱活动有关,亦或是其他作用导致的拉张环境.钾霞橄黄长岩在地幔源区、岩石成因和构造环境等方面尚存争议,有待进一步研究.As a kind of ultrabasic ultramafic volcanic rock with low SiO_(2)and Al_(2)O_(3)contents and high alkali contents,Kamafugite is an important window to investigate the mantle.This paper summarized the research results of kamafugite at home and abroad,compared and analyzed the petrology,whole-rock geochemistry,and isotopic characteristics of kamafugite in different regions.The results show that the kamafugite is mainly composed of olivine,phlogopite,leucite,potassium feldspar,and pyroxene minerals.Kamafugite is highly enriched in incompatible trace elements,which shows the characteristics of the enriched mantle,but the Italian kamafugite is depleted in Nb,Ta,Zr,Hf,and other high field elements,while the Chinese kamafugite has the isotopic characteristics of the depleted mantle.Based on the geochemical analysis,it is generally believed that kamafugite is probably formed in an extensional environment,during the post-collision stage of orogenesis,or concerning mantle plume activity,or caused by other actions.There are still some controversies about the mantle source,petrogenesis,and tectonic environment of kamafugite,which need to be further studied.

关 键 词：钾霞橄黄长岩 地球化学 成因 构造背景 

分 类 号：P588.1[天文地球—岩石学]