【摘要】 地球动力环境对岩浆来源和侵位机制具有重要的控制作用.铜陵矿集区中生代中酸性侵入岩和大规模成矿作用有密切关系.凤凰山岩体为凤凰山矿田的主要组成部分,主要岩石类型为花岗闪长岩、石英二长闪长岩.根据精确锆石SHRIMP测年结果,凤凰山岩体206Pb/238U年龄为(144.2±2.3)Ma,是晚侏罗世形成的一个典型岩体,和铜陵矿集区主要成矿岩体的形成时代一致.接触带构造变形特征显示岩体侵位受控于区域左旋剪切应力场作用.内部构造变形特征表明凤凰山岩体在深部主要为左旋螺旋式强力上升,浅部为气球膨胀式主动侵位.岩体形成时代及构造变形特征表现出晚侏罗世铜陵矿集区和成矿有关的侵入岩系列的形成可能和古太平洋板块的向北斜向俯冲所导致的左旋剪切应力场有关.更多还原

【Abstract】 Geodynamic settings play an important role in controlling generation, ascent and final emplacement of magma. Mesozoic intermediate-acid intrusive rocks are closely related with large scale mineralization in the Tongling metallogenic cluster area. The Fenghuangshan pluton, which consists of granodiorite and quartz monzodiorite, is the main part of the Fenghuangshan ore field. Zircon SHRIMP ~ 206 Pb/~ 238 U dating shows that the Fenghuangshan pluton formed at (144.2±2.3)Ma, belonging to the Late Jurassic era, which is in accordance with most of metallogenic plutons of the Tongling metallogenic cluster area. The contact deformation shows that the Fenghuangshan pluton was controlled by a regional sinistral shear stress field. The internal deformation indicates that the pluton experienced sinistral spiral ascent and final ballooning emplacement. The age and structural deformation imply that the Late Jurassic pluton related to mineralization may correlate with sinistral shear stress field induced by the northward oblique subduction of the paleo-Pacific plate.更多还原