CAJ | 학술논문

西秦岭北缘新阳-元龙大型韧性剪切带是分划西秦岭造山带与祁连造山带的区域主构造边界,通过对其物质组成和构造特征的研究,结合两侧不同(洋-陆)构造环境下各类地质体的研究成果,重点对剪切带内花岗质糜棱岩中黑云母单矿物进行了~(40)Ar-~(39)Ar定年研究.在新阳镇和元龙北剪切带中分别获得(347.95±2.17)Ma (MSWD＝1.89)和(351.70±1.72)Ma (MSWD＝0.80)的坪年龄,分析确定其应为黑云母的冷却年龄,表明变形时代应在早石炭世早期之前;反映了最晚在早石炭世早期,该剪切带已横切秦岭与祁连造山带并发生强烈的右行走滑构造拼贴作用.
서진령북연신양-원룡대형인성전절대시분화서진령조산대여기련조산대적구역주구조변계,통과대기물질조성화구조특정적연구,결합량측불동(양-륙)구조배경하각류지질체적연구성과,중점대전절대내화강질미릉암중흑운모단광물진행료~(40)Ar-~(39)Ar정년연구.재신양진화원룡북전절대중분별획득(347.95±2.17)Ma (MSWD＝1.89)화(351.70±1.72)Ma (MSWD＝0.80)적평년령,분석학정기응위흑운모적냉각년령,표명변형시대응재조석탄세조기지전;반영료최만재조석탄세조기,해전절대이횡절진령여기련조산대병발생강렬적우행주활구조병첩작용.
The Xinyang-Yuanlong ductile shear zone in the north margin of West Qinling is the main tectonic boundary which partitions the West Qinling orogenic belt from the Qilian Orogenic belt. Their material composition and tectonic characteristics were studied in this study combined with the study results of various blocks in different tectonic settings (ocean-continent) of both side. This study also focused on ~(40)Ar-~(39)Ar dating of the biotite from granitic mylonite in the shear zone and yielded plateau ages of 347.95±2.17Ma (MSWD＝1.89) and 351.70±1.72Ma (MSWD＝0.80)for Xinyang Town and the shear zone of northern Yuanlong respectively. They are identified as cooling ages of the biotites, indicating that the time of deformation should earlier than the early period of Early Carboniferous. The research shows that it was at least at the early Carboniferous that the shear zone cut across the Qinling orogenic belt and the Qilian Orogenic belt and underwent intense dextral strike slipping and tectonic matching in the early period of Early Carboniferous at the latest,.