摘要
滇西保山地区晚石炭世火山岩主要以基性熔岩——玄武岩为主。该区玄武岩分为东、西两个岩带,西岩上在剖面结构、喷发韵律、旋回、环境方面均有差异,但两岩带玄武岩都起源于原始地幔的低程度部分熔融。保山玄武岩的地球化学特征均与大陆溢流玄武岩(高原玄武岩)相似,其产出的构造环境是大陆板内断裂岩浆活动。
The Upper Carboniferous volcanic rocks in Baoshan are mainly from widely erupted basiclavas. The basalt can be divided into east and west belts. Two belts are different in sequences, eruptionrhythms, eruption cycles, and environments. The lower part of basalt is of primary origin, showingweak crystallization differentiation. The middle-upper part of bssalt has been evolved in some degree.The two belts were formed by homologous magmatism, arised from weakly pertial fusion of primarymantle. The features of geochemistry of Baaoshan basalt are similar to plateau basalts, The tectonic en-vironment of the basalt is stable continental crust with fracturing-magmatism.
基金
国家自然科学基金
关键词
晚石炭世
火山岩
构造
环境
Baoshan
basalt
main elements
trace elements
tectonic environment
