摘要
滇西富碱斑岩带形成于新生代 (年龄为 2 3.18～ 6 2Ma) ,沿金沙江 -哀牢山断裂带分布。对其岩石化学、同位素地球化学等方面的研究表明其总体处于剪切挤压为主、局部引张的构造环境中 ,苍山等地元古宙基底变质岩的穿刺 (翘起 )就是挤压环境下的产物之一 ;富碱斑岩是深部交代的富集地幔 (EMⅡ )流体上侵经地壳物质不同程度混染的产物 ,扬子陆块和冈瓦纳大陆的组分对新生代岩浆活动均产生影响。
Distributed along the Jinshajiang-Ailaoshan fault zone, the alkaline_rich porphyry zone was formed in Paleogene (from 62 Ma to 23.18 Ma). The petrochemical and isotopic geochemical characteristics of the porphyriessuggest that the tectonic setting is predominantly shear_compression and locally extension, uplifting (diapir) of the Protererzoic basement metamorphic rocks of Mt. Cangshan is also a product of the same setting. The alkaline_rich porphyry results from upward erosion of deep EMⅡ fluid contaminated in different degrees by crustal components. Porphyries keep a trace of both Yangtze block and Gandwana continent, as shown by lead isotopes.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2002年第3期231-241,共11页
Acta Petrologica et Mineralogica
基金
国土资源部资源与环境科技攻关资助项目 (95 - 0 2 - 0 0 1- 0 2 )
关键词
挤压走滑
PB同位素
富碱斑岩
苍山
金沙江-哀牢山断裂
云南
钕同位素
锶同位素
compression strike_slip setting
Nd, Sr, Pb isotopes
alkaline_rich porphyries
diapir of Mt. Cangshan
Jinshajiang-Ailaoshan fault zone
western Yunnan
