九岭南缘安义珠洛山辉绿岩形成时代及地质意义  

Forming Era and their Geological Significance of Diabase in Zhulou Mountain at the South Edge of JiuLing Mountain

作　　者：张芳荣 刘前进 

机构地区：[1]江西省地质调查院,江西南昌330001

出　　处：《东华理工学院学报》2007年第4期328-331,340,共5页Journal of East China Institute of Technology

基　　金：国土资源大调查项目(200113000011)

摘　　要：扬子地台周边地区已陆续发现基性—超基性岩,但其成因一直存在争议。九岭南缘安义珠洛山变质基底地层中也发育有辉绿岩岩墙群,其形成时代及成因未作过研究。笔者通过1∶25万上高县幅区域地质调查,获得其单颗粒锆石U-Pb法同位素年龄为(796±1)Ma,属新元古代基性岩。该基性岩岩墙群地球化学成分相当于拉斑玄武岩序列,形成于板内环境。它与九岭强过铝质花岗岩构成双峰式侵入岩套,可能形成于碰撞后伸展构造环境,而与Rod in ia超大陆裂解无关。Basic-ultrabasic rocks are discovered in succession in neighboring area of Yangtze platform, but their origins have being disputed. The diabase dike group is developed in metamorphic basement in Zhulou Mountain at the South Edge of Jiuling Mountain, their forming era and their origins have not been researched. During the in- vestigation of regional geology of Shanggao County sheet of 1 ： 250 000, the dating of single zircon gained by the writer is 796 ± 1 Ma, belonging to neoproterozoic basicrock. Geochemistry compositions of the basicrocks group are corresponding to the sequence of tholeiite, derived from intra-block setting. They constitutes hi-modal rock- suit associating with strongly peraluminous granites in Jiuling Mountain, perhaps derived from the post-collsional tectonic setting, and are not related with the breakup of the super-continent Rodinia.

关 键 词：地质意义 形成时代 辉绿岩 珠洛山 九岭南缘 

分 类 号：P56[天文地球—构造地质学]