Stress and Deformation Characteristics of the Central‐Southern Tibetan Crust: Insights From Electrical Anisotropy Studies

作者：Zhehan Liu, Hao Dong, Sheng Jin, Wenbo Wei, Gaofeng Ye, Letian Zhang · 发表于：Journal of Geophysical Research Solid Earth · 年份：2026 · DOI：10.1029/2024jb030594 · 被引用次数：1 · 研究领域：Geophysical and Geoelectrical Methods、High-pressure geophysics and materials、Earthquake Detection and Analysis

Abstract Mechanisms governing the stress‐induced surface deformation of the Tibetan Plateau and other continental collision zones remain vigorously debated in the geoscience community. Crustal rheological properties can offer valuable insights into the Earth's deformation patterns. Here, we present an electrical anisotropic study of the crust and upper mantle along a profile in the central‐southern Tibetan Plateau. Our resistivity models unveil a large‐scale conductive layer beneath the study region, with distinct electric anisotropic orientations within the middle and lower crust. The middle crust exhibits nearly north–south (N–S) directed anisotropy features, whereas the lower crust anisotropy axis is east–west (E–W) directed. From the conductivity model, we estimate the melt fraction and viscosity distribution using an experiment‐based empirical formulation. As demonstrated by the petrological experiments, the amphibole‐rich mid‐to‐lower crust could host the aligned fractures/microcracks and melt pockets, possibly facilitating the observed anisotropy. With an anisotropic conduction model, we also show that the distribution characteristics of these cracks and pockets may directly influence the effective conductivity. The two‐layered electrical anisotropy observed likely reflects distinct deformation types and rheological strengths: the N–S electrical anisotropy may originate from fluid‐filled fractures from the brittle deformation in the middle, while the E–W anisotropy may...