Structural and geochronological constraints on a Late Mesozoic extension event in the West Qinling Orogenic Belt, China

• DOI: 10.5194/egusphere-egu22-11808
• Publication Date: 2022-03-28T02:37:37Z
• Authors: Le Zhang; Wei Li
• Keywords: Orogeny; Geochronology

<p>The Qinling Orogenic Belt (QOB) has been well documented that it was formed by multiple steps of convergence and subsequent collision between the North China Block (NCB) South (SCB) during Paleozoic Late Triassic. Following in Triassic, whole QOB evolved into an intracontinental orogeny. Large-scale N-S compressional thrusting deformation tectonics along previous major boundary faults were developed. Meanwhile, several extension-related also developed or slightly later than compression. However, expiry date Mesozoic compression orogeny tectonic transformation remains unclear.</p><p>The extensional shear zone West provides a crucial clue for revealing orogenic belt's uplift exhumation process. This paper focuses on kinematics, geochronology, temperature Taibai west (TBSZ) to understand evolutionary process QOB.</p><p>The at northwestern margin pluton. It cuts across separates pluton east from Baoji west. The NE–NEE-striking NW–NNW-dipping TBSZ is showing top-to-the-NW sinistral sense. Mineral characteristics two-feldspar geothermometers constrain under high greenschist–low amphibolite facies conditions (300-550 ℃) middle-upper crust (8-15 km). Zircon U-Pb dating biotites muscovites <sup>40</sup>Ar-<sup>39</sup>Ar analysis suggest uplifted rapidly 120-113 Ma.</p><p>Combined with regional geological data, records collapse belt 120–113 Ma. led rapid east.</p>