Abstract: The Liao-Meng geological corridor, which centers on western Liaoning and extends 800 km in a nearly E-W direction, was selected as the study area. Through a chronological study, the authors confirm that the symmetrical temporal-spatial distribution pattern of Meso-Cenozoic volcanic activities since 130 Ma has the features of being “older (Mesozoic) in the center and younger (Cenozoic) at both sides”, and with time the magma derived from the asthenosphere flowed laterally toward the east and west and the magma source deepened continuously. On that basis, the authors propose a model of “upwelling and lateral flow of the asthenospheric diapir”.