The Curie Surface and Lithospheric Thermal Structure in Mongolia‐Baikal Region

Abstract

AbstractThe Mongolia‐Baikal region, located between the Siberia, North China, and Tarim cratons, exhibits the most pronounced lithospheric accretion and extension since the Phanerozoic. Despite its distance from plate boundaries, the region's notable tectonic activity underscores its importance for studying intraplate lithospheric deformation. However, its lithospheric thermal structure, particularly at high resolution, remains inadequately characterized. By integrating magnetic anomaly constraints with heat flow measurements, we have obtained a high‐resolution lithospheric thermal structure for the Mongolia‐Baikal region, revealing lithospheric thicknesses ranging from 60 to 180 km. The Curie depth and mantle heat flow also show diverse variations across different regions. Our results suggest that elevated mantle heat flow in the Baikal Rift Zone, coupled with a uniform Curie depth and minimal lithospheric thinning, likely reflects lithospheric weakening from mantle upwelling, facilitating rifting in the early stages of the rift's formation. Additionally, some localized lithospheric thermal variations identified in our results may be closely linked to the formation of the Hangai Plateau and the low magnetic anomalies observed in the Mongolia‐Okhotsk suture.