3D Crustal and Upper Mantle Model of East‐Central China From a Joint Inversion of Surface and Body Waves and Its Tectonic Implications

Abstract

The major geological units in East-Central China include the North China Craton (NCC), the South China Block (SCB), and the Qinling-Dabie-Sulu orogen formed by the collision of the NCC and SCB (Figure 1). During the Late Paleozoic to Triassic, as the Paleo-Tethys Ocean closed, the SCB collided with and subducted under the NCC (e.g., S. Li et al., 1993;Meng & Zhang, 2000;Y. F. Zheng et al., 2003). During the Jurassic to Early Cretaceous, influenced by the subduction and retreat of the Paleo-Pacific plate, East China developed extensive magmatic activities, which is strongly associated with the destruction of the NCC (Zhu & Xu, 2019), the intensive post-collision magmatism in the Dabie and Sulu orogen (Z. F. Zhao et al., 2013), and the rich mineral resources in the Middle-Lower Yangtze River Metallogenic Belt (Lü et al., 2015). During the Late Cretaceous, East China was in a period of tectonic quiescence. Until the Cenozoic, the Pacific plate began to subduct and retreat, resulting in a large-scale eruption of Cenozoic continental basalts in East China (Y. Xu et al., 2018;. Additionally, the far-field impact of the India-Eurasia plate collision during the Cenozoic also needs to be considered.

Continental Reworking in the Eastern South China Block and Its Adjacent Areas Revealed by F‐J Multimodal Ambient Noise Tomography

“…These two events may not have a huge influence on continental reworking in the eastern SCB and its adjacent areas because the Cenozoic magmatic rocks (<50 Ma, area B in Figure 19d) are only distributed in the northern margin of the NCB and near the Tanlu fault zone. The concentrated distribution of Cenozoic magmatic rocks may indicate that the Cenozoic tectonic activities further promote the upwelling of hot asthenosphere materials (Yang et al., 2021) along the Tanlu fault zone. However, the subduction of the Pacific plate since the late Mesozoic, as discussed above, played a crucial role in continental reworking for the eastern SCB and adjacent areas because of its distinctly extensive influence.…”