Discovery and significance of Lizifang metamorphic core complex in Zhuanghe area of southern Liaoning
ZHONG Mishan1, 2, ZHANG Guoren2, WU Zijie2, 3, GAO Fuliang2, MA Ningning4, PAN Yuqi2, GAO Yongzhao2
1. College of Earth Sciences, Jilin University, Changchun 130061, China; 2. Liaoning Provincial Institute of Geological Exploration LLC, Dalian 116100, China; 3. School of Geosciences, China University of Petroleum(East China),Qingdao 266580, China; 4. Shandong Institute of Geological Surveying and Mapping, Jinan 250000, China
Abstract:On the basis of the previous regional geological survey, based on the macroscopic and microscopic structural survey, combined with the comprehensive analysis of the regional magmatic activity and dating data, the authors in this paper revealed that there is another metamorphic core complex structure in Lizifang area of Southern Liaoning, namely Lizifang metamorphic core complex. A typical three-layer structure and five parts exist in the core complex, which are the footwall composed of Neo-archean metamorphic plutonic rocks and mesozoic granite intrusive rocks, the detachment fault zone composed of different levels of tectonic rocks, and the upper plate composed of Precambrian sedimentary cap and Cretaceous extensional basin. Lizifang metamorphic core complex formed in the Early Cretaceous Epoch, and the upper plate moved from NWW to SEE relaive to the footwall, which was similar with Jinzhou metamorphic core complex and Wanfu metamorphic core complex in geometry, kinematics polarity and formation time, indicating the same dynamic background. The determination of the metamorphic core complex may provide a basis for the late Mesozoic lithospheric thinning process and the mechanical and rheological properties of the lithosphere in the east of North China Craton. At the same time, the metamorphic core complex is closely related to the mineralization of gold deposits. So the detachment fault zone of Lizifang metamorphic core complex can serve as the key work area for further gold exploration, which may possess large mineralization potential.
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