Lithospheric Thermal and Compositional Structure of Northeast China: Implications for Lithospheric Thinning

Summary Northeast China, with its complicated regional tectonic evolution, situated within the eastern Central Asian Orogenic Belt, is a key region for understanding lithospheric deformation and mantle dynamics. However, the ongoing debate surrounding its lithospheric structure and evolutionary processes remains, largely attributed to data limitations and methodological constraints. In this study, we integrate topography, geoid height, surface heat flow, and Rayleigh wave phase velocity dispersion curves to conduct a detailed imaging of the lithospheric thermal and compositional structure in Northeast China. We find a significant east-west gradient in lithospheric thickness, ranging from approximately 60 km in the east to 140 km in the west, and a compositional transition in the lithospheric mantle from fertile peridotite in the east to refractory peridotite in the west. By integrating analyses of upper mantle anisotropy and the spatiotemporal distribution of Mesozoic basalts, we argue that the lithospheric delamination and mantle upwelling may have combined to cause the lithospheric thinning in the region. This study highlights the significance of joint inversion of multiple datasets and integrated multidisciplinary analysis.