摘要
琼中地区琼中岩体为钙碱性的铝弱过饱和型花岗岩,具有壳源物质来源,岩石普遍发育定向组构,生成于同碰撞期-晚造山期.其锆石U-Pb年龄为226.5±2.9～234.2±2.3Ma,为晚三叠世.通过区域分析,认为海南岛海西-印支期花岗岩从西往东,具有由老至新的演化规律,形成了略向南面突出的弧状面理构造.表明同期造山活动消减方向由西至东,呈现出剪刀式闭合的特征.
Qiongzhong pluton was formed by slender supersaturation calc-alkalic granites, with involvement of crustal materials in the rock constituents. Orientated fabrics are very common, which suggests that it was formed during apposition-collision in the late orogenic period. The Zircon U-Pb dating gives results of 226.5±2.9 - 234.2±2.3 Ma, indicating that it belongs to Late Triassic. Regional geological study suggests that from east to west the Hercynian-Indosinian granites in Hainan Island show an evolution trend of increasingly younger ages and demonstrate an arc-shaped foliation structure. These suggest that the termination direction of the orogenic movement is characterized by shear convergence extending from west to east.
出处
《大地构造与成矿学》
EI
CAS
CSCD
北大核心
2005年第2期227-233,241,共8页
Geotectonica et Metallogenia
关键词
岩体时代
地质意义
海南岛
pluton age
geological significance
Hainan island
