江西暖水地区韧性剪切带的基本特征和形变机制

The Basic Characteristics and Deformation Mechanism of the Ductile Shear Zone in the Area of Nuanshui,Jiangxi Province

在进行暖水幅1:5万区调时发现江西暖水地区赣东北断裂带中存在外富家坞—枫坡岭、昭林、牛角垄—下石坞三条平行韧性剪切带,为进一步研究暖水地区韧性剪切带岩石、构造形变机制、形成时代特征及与赣东北断裂带的关系,通过地质、岩石矿物、测试分析等综合研究表明,韧性剪切带主要由千糜岩带、糜棱岩带、初糜棱岩带、糜棱岩化带、强片理化带及碎裂岩带组成,其形成经历了早期深层次韧性变形到晚期浅层次脆性变形两个阶段,形成深度10～20km,是赣东北断裂带的主要组成部分,主要变形时代为中晚元古代,与这一时期的华夏板块和扬子板块之间的相互作用有关。

When Nuanshui 1 ： 50 000 regional geological survey found that there exist the three parallel ductile shear band which are Fujiawu-Fengpolin, Zhaolin, Niujiaolong-Xiashiwu inside the north-eastern Jiangxi fault in the area of Nuanshui, Jiangxi Province. To further research on the rocks, tectonic deformation mechanism, the characteristicsthe of formation times of the ductile shear zone in the area and the relationship between it and the northeastern Jiangxi fault zone, comprehensive study of methods （include geology, rock minerals, test analysis, etc. ） have been used. The results show that the ductile shear zone are made of the phyllonite band, mylonite band, protomylonite band, mylonitization band, strong schistosity band and cataclasite band. The formation of the Nuanshui ductile shear zone has experienced two stage which the early is dcep-seated ductile deformation and the late is shallow-seated brittle deformation, but the main deformation is in the age of middle-late Proterozoic during this period the interaction of Chinese plate and Yangtze plate that has related. It forms the depth of 10 -20 km and is the main components of the north-eastern Jiangxi fault zone.