摘要
景德镇韧性剪切带位于新元古代江南造山带的核部,其构造变形特征和形成时代对华南新元古代至早古生代构造演化具有重要的制约意义。景德镇韧性剪切带呈北东向展布,全长约180 km,最大出露宽度为~7 km。通过详细的野外地质调查和室内定向薄片鉴定,在景德镇韧性剪切带中识别出了两期韧性走滑构造变形,并研究了其运动学指向和形成时的温压条件。早期构造变形表现为左旋韧性走滑兼逆冲作用,形成温度为420~530℃,差应力为40~300 MPa;晚期变形主要表现为右旋走滑,形成温度为300~420℃,差应力为120~350 MPa。结合前人资料,景德镇韧性剪切带左旋走滑兼逆冲作用形成于新元古代造山作用的晚期(810~800 Ma),是由同造山挤压到后造山伸展调整的结果;而右旋走滑形成于早古生代,是华南早古生代陆内造山作用的产物。
The Jingdezhen ductile shear zone is located at the core of the Neoproterozoic Jiangnan Orogen.Structural features andgeochronology of the Jingdezhen ductile shear zone have a key implication for the Neoproterozoic to Early Paleozoic tectonic evolutionof the South China Block.The Jingdezhen ductile shear zone is~180 km long in the NE-striking orientation and~7 km in maximumwidth.Two-phase ductile strike-slip shearing was identified based on detailed field investigation and observation of oriented thinsections.Moreover,the kinematic indicators and temperature-pressure conditions were studied in this paper.The early sinistral ductilestrike-slip with thrusting occurred at 400~500℃and differential stress of 40~300 MPa,whereas the dextral ductile shearing at 300~400℃and differential stress of 120~300 MPa.Combined with the previous work,the sinistral strike-slip with thrusting of theJingdezhen ductile shear zone took place at late stage of the Neoproterozoic orogen in the South China Block(810~800 Ma),as a resultof transformation from syn-orogeny compression to post-orogeny extension.The dextral shearing of the Jingdezhen ductile shear zoneoccurred in the Early Paleozoic,triggered by the Early Paleozoic intracontinental orogeny of southeast China.
作者
徐先兵
汤帅
林寿发
XU Xianbing;TANG Shuai;Lin Shoufa(School of Earth Sciences,China University of Geosciences,Wuhan 430074,China;Department of Earth and Environmental Sciences,University of Waterloo,Ontario N2L 3G1,Canada)
出处
《高校地质学报》
CAS
CSCD
北大核心
2016年第2期308-316,共9页
Geological Journal of China Universities
基金
国家自然科学基金青年基金项目(41402174)
关键词
运动学指向
温压条件
景德镇韧性剪切带
江南造山带
华南
kinematic indicator
temperature-pressure condition
Jingdezhen ductile shear zone
Neoproterozoic Jiangnan Orogen
South China Block
