摘要
岩浆混合花岗岩主要是指壳源酸性岩浆与幔源基性岩浆,经岩浆混合作用形成的复杂混合花岗岩类。两类岩浆混合及成岩过程中,有显著的元素迁移、成分交换和双扩散。被誉为地球化学指示剂、示踪剂的微量元素,是岩浆混合、成岩作用及岩浆演化这一过程的最好记录,因而其参数和有关图解可提供岩浆混合的成因判别信息。以西秦岭温泉岩浆混合花岗岩为例,介绍了微量元素岩浆混合成因的地球化学证据,讨论了成岩过程中微量元素的双扩散特征,得出了Sr-微量元素组合图解方法,极容易对岩浆混合花岗岩的成因进行区分和识别,这一方法为岩浆混合花岗岩的直观判别、图解化分类以及深入研究提供了重要的地球化学信息和新途径。
Mixing and mingling granites mostly mean the complex one formed by the crust origined magma mingled with the mantle origined magma and vice versa.During the mingling and diagenesis, there were noticeable elements transfering, component exchanging and double diffusing . Therefore, trace elements, acting as indicators, can offer the information of the origin discriminantion by using parameters and relevant diagram. Exampified by the wenquan granite and based on evidences of trace elements geochemistry of mixing genesis and double diffusing characteristics of diagenesis, the right angle coordinate system using the Sr the other trace elements in the diagram is obvious that trace elements illustration can easily identify genesis of mixing granites. This method not only supplies object discriminantion and illustrated classification, but also provides important geochemistry information and new reproach for thorough study of mixing granites.
基金
国土资源部地质调查项目(20001300010171)
关键词
岩浆混合花岗岩
微量元素
成因
图解
双扩散
mixing and mingling
granite
trace elements
double diffusing
genesis illustration
