Lake Unloading Drives Fault Slip and Rift Asymmetry in Southern Tibet

Abstract The extent to which surface processes drive continental deformation remains a pivotal question in geodynamics. Here, we demonstrate that Late Quaternary lake‐water unloading is a primary driver of fault slip and rift asymmetry in southern Tibet. Since the last interglacial (∼116 ka), significant water‐level drops of large lakes have induced crustal rebound and Coulomb stress changes. At Nam Co Lake, a ∼130 m drop produced ∼0.1 MPa of stress change, preferentially reactivating the adjacent fault and contributing ∼15 m of vertical displacement ∼23% of the total near Damxung. Likewise, the southern lakes (Yamzho Yumco and Puma Yumco) caused ∼70 m of vertical displacement on the adjacent fault. We establish that climatically‐controlled lake unloading can directly shape continental rifting by selectively enhancing fault slip on the lake‐bounding side of the rift, thereby amplifying its structural asymmetry. This highlights a significant, quantifiable role of surface processes in actively shaping tectonic deformation.