摘要
岩石学、岩石地球化学研究表明,东昆中隆起带东段分布一套高钾的钙碱性闪长岩系列岩石。岩石明显富集大离子亲石元素(如K、Ba、Rb)、LREE和活泼的不相容元素(如Th、U),相对亏损高场强元素(如Nb、Ta、Ti、P),具安第斯型活动大陆边缘岩浆岩特征。该闪长岩属混合成因,即由交代地幔的部分熔融形成基性岩浆,与地壳物质熔融形成的酸性岩浆混合形成。阿斯哈闪长岩LA-ICP-MS锆石U-Pb年龄值为244Ma左右,属印支早期。
Studies of petrology and geochemistry indicate the high-K calc-alkaline diorite groups are located in the eastern section from eastern Kunlun middle uplifted basement and granitic belt,This suite of dioritic rocks are enriched in LILE（such as K,Ba,Rb）,LREE and more mobile incompatible elements（such as Th,U）,relatively depleting in HFSE（such as Nb,Ta,Ti,P）,similar to the characteristics of Andean-type active continental margin magma,It is suggested that a mixture,between basaltic magma derived from partial melting of metasomatized mantle and acidic magma derived from crustal material,produces the dioritic magma,LA-ICP-MS zircon U-Pb dating shows that the diorite in the Asiha intrusions was formed at ～244Ma,which in Early Indosinian period.
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第4期1163-1172,共10页
Acta Petrologica Sinica
基金
中国地质调查局地质大调查项目(1212011086020)资助
关键词
高钾钙碱性侵入岩
岩石成因
构造背景
U-PB年龄
东昆中隆起带
K-rich calc-alkaline intrusion
Petrogenesis
Tectonics setting
U-Pb dating
Eastern Kunlun middle uplifted basement and granitic belt
