The spatial distribution of the channel flow in the southeastern margin of the Qinghai-Xizang Plateau has received significant attention in recent years. Previous studies have employed different geophysical methods to describe the different forms of channel flow. In this study, channel flow is examined using the flexural isostatic method. Using the Fan wavelet method, we calculate the correlation between gravity and topographic data, namely the admittance and coherence. Inversion experiments are conducted on various combinations of admittances and coherences of Free-air gravity anomalies (FGAs) and Bouguer gravity anomalies (BGAs) using simulated data. The results show that the joint inversion of FGAs and BGAs coherences can recover the optimal distribution of the lower crustal internal load ratio , which quantifies the contribution of loading from the internal density interface during isostatic adjustment and indicates the channel flow at the lower crust, explaining crustal uplift. The new FGAs and BGAs field of the southeastern margin of the Qinghai-Xizang Plateau are derived by merging the survey and model data. The joint inversion method, combined with digital elevation and merged gravity anomaly data, is then used to invert the distribution of the lower crustal internal load ratio. The result indicates that the channel flow rotates clockwise around the eastern Himalayan syntaxis, migrating from the interior of the Qinghai-Xizang Plateau toward its southeastern margin.
She et al. (Sun,) studied this question.