Piecemeal Delamination of Thickened Lithosphere Triggered Pulsed Magmatism and Mineralization during Late Mesozoic Intracontinental Orogeny in East Asia

Abstract

The East Asia continent is characterized by a mosaic architecture with various composing blocks, such as the North and South China blocks, which had been collaged in Late Permian to Triassic in response to the break-up of Pangea. In the Late Mesozoic, this continent was still in multi-plate convergent tectonics, surrounded by three oceans (Dong et al., 2008(Dong et al., , 2018. The convergence between the amalgamated Siberia and the composite North China-Mongolia Block led to the eastward scissors-like closure of the Mongol-Okhotsk ocean in the Middle-Late Jurassic to Early Cretaceous and gave rise to the Mongol-Okhotsk orogeny. To the southwest, the closure of the Neo -Tethyan ocean led to accretion of the Lhasa block to the Eurasia along the Bangonghu-Nvjiang suture in the Late Jurassic to Early Cretaceous. The eastern part of the East Asia continent evolved to a broad, active magmatic margin due to westward subduction of the Paleo-Pacific oceanic plate in Jurassic to Early Cretaceous.

Thermo‐Kinematic Constraints on Restoration of the Eastern Sichuan Fold‐And‐Thrust Belt, South China

“…During the Late Jurassic, South China evolved into an Andean‐type active margin due to the approximately northwestward subduction of the Paleo‐Pacific Plate (C. H. Xu et al., 2017). The synchronous convergence generated distant effects, including intracontinental deformation and associated magmatism, during the Yanshanian orogeny (Y. Q. Zhang et al., 2021). The continued northwestward subduction of the Paleo‐Pacific Plate resulted in northwestward shortening across South China in the Late Jurassic.…”

“…In this study, balanced‐section restoration of profile A‐A' is calibrated with the thermo‐kinematic model using combined results of analog models, DEM, and thermochronology data. By compiling surface structural geology and age data set of Late Mesozoic magmatic rocks in South China, a single distinctive tectonic switch at ∼170 Ma was defined and it is generally believed that significant crustal shortening occurred during the period of 170–135 Ma, followed by crustal extension during the period of 135–80 Ma (Chu et al., 2019; J. H. Li et al., 2020; Y. Q. Zhang et al., 2021). It is generally believed that the Mesozoic crustal shortening and extension resulted in the establishment of the ESFTB (Chu et al., 2019; C. X. Li et al., 2021; Yan et al., 2003, 2009; Zhou and Zhou, 2022).…”

“…The synchronous convergence generated distant effects, including intracontinental deformation and associated magmatism, during the Yanshanian orogeny (Y. Q. Zhang et al, 2021). The continued northwestward subduction of the Paleo-Pacific Plate resulted in northwestward shortening across South China in the Late Jurassic.…”

Tensile Fractures and in situ Stress Measurement Data Constraints on Cretaceous–Present Tectonic Stress Field Evolution of the Tanlu Fault Zone in Shandong Province, North China Craton

“…The second stage is dominated by the Early Cretaceous Guojialing granites and granitic diorites that were emplaced during 130-126 Ma, as revealed by 11 zircon SHRIMP geochronological data (Wang et al, 2021). These granites and diorites were derived from the vast lithospheric thinning that occurred during the tectonic transition from compression to extension, due to the continental arc settings (Zhang et al, 2021). The third stage is characterized by the Weideshan diorites, granitic diorites, and granites and Laoshan alkaline granites.…”