New Discovery of ∼1866 Ma High‐temperature Mylonite in the Helanshan Complex: Marking a Late‐stage Ductile Shearing in the Khondalite Belt, North China Craton
New Discovery of ∼1866 Ma High‐temperature Mylonite in the Helanshan Complex: Marking a Late‐stage Ductile Shearing in the Khondalite Belt, North China Craton
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DOI：
10.1111/1755-6724.14749
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发表时间：
2021-06
期刊：
影响因子：
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通讯作者：
Hengzhong Qiao;C. Yin;Jian Zhang;J. Qian;Shangjing Wu
中科院分区：
文献类型：
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作者：
Hengzhong Qiao;C. Yin;Jian Zhang;J. Qian;Shangjing Wu
孔兹岩带是华北陆块西部古元古代喜马拉雅型近东西向造山带。认为这是北方阴山地块与鄂尔多斯地块在~1.95 Ga发生碰撞的结果，碰撞导致了西部地块的统一基底（例如，Zhao等人，2005年; Yin等人，2011年）。孔兹岩带经历了长期的陆-陆碰撞造山作用，发育了一系列引人注目的晚期平行造山韧性剪切带（如，Huang等人，2013年; Gong等人，2014年）。然而，由于缺乏地质年代学数据，这些韧性剪切变形的时间受到很大的限制。这不可避免地妨碍了对孔兹岩带变形历史的全面认识。因此，我们对孔兹岩带最西端贺兰山杂岩中古元古代韧性剪切带中的高温糜棱岩进行了锆石U-Pb定年。这些资料将为孔兹岩带古元古代构造演化提供新的认识。
The Khondalite Belt is a nearly E–W-trending Paleoproterozoic Himalayan-type orogen in the Western Block of the North China Craton. It is regarded as a result of the collision between the northern Yinshan Block and the southern Ordos Block at ~1.95 Ga, which led to the formation of the united basement of the Western Block (e.g., Zhao et al., 2005; Yin et al., 2011). The Khondalite Belt has undergone long-term continent-continent collisional orogenic processes, and a remarkable series of late-stage orogen-parallel ductile shear zones developed (e.g., Huang et al., 2013; Gong et al., 2014). However, the timing of these ductile shear deformations was poorly constrained because of the lack of geochronological data. This inevitably hampers a comprehensive understanding of the deformation history of the Khondalite Belt. Therefore, we carried out zircon U-Pb dating of a hightemperature mylonite from the Paleoproterozoic ductile shear zones in the Helanshan Complex, the westernmost part of the Khondalite Belt. These data will shed new light on the Paleoproterozoic tectonic evolution of the Khondalite Belt.