Structural analysis and new zircon U/Pb geochronology were performed in the Cuonadong Dome in order to test the hypothesis that the top‐to‐North deformation in the North Himalayan Gneiss Domes (NHGD) has been correlated with deformation along the South Tibetan detachment system (STDS). Structural analysis suggests that the X‐axes of sheath folds at the different flanks of the dome are consistent, and show average a trend and plunge of 350° and 18°. Many shear sense indicators are recorded in the ductile shear zone during the top‐to‐north deformation, including the augen structure, σ‐type and δ‐type rotating porphyroclast, S–C fabric and pressure shadow structure. The development of the sheath folds first provide a direct‐field structural evidence that represents a deeper ductile manifestation of the STDS, and further suggests that the top‐to‐north deformation in the NHGD have been correlated with deformation along the STDS. The emplacement of the synkinematic granites at ca. 32 Ma exposed at the core of the sheath folds is also interpreted as the initiation of slip along the STDS.

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The Cuonadong dome located at the eastern part of Tethyan Himalaya consists of three lithologic‐tectonic units from the inside to the outside: the lower, middle, and upper units. The large‐scale Cuonadong Be‐W‐Sn deposits are hosted in the strong shear zone of the middle unit of the dome. In this study, multi‐scale gravity and magnetotelluric data were used to generate two‐dimensional electrical resistivity models and three‐dimensional density models for the deep structure of the Cuonadong dome. The results show that interpretation of geophysical data on the deep structure is largely consistent with the three lithologic‐tectonic units in the dome. The lower unit consists of gneiss and leucogranites that are characterized by high electrical resistivity. Schist, skarn, and marble in the middle unit exhibit moderate electrical resistivity, and Be‐W‐Sn rare metal bodies are hosted in skarn and marble. The sedimentary rocks of the upper unit are characterized by low electrical resistivity. Therefore, we proposed a geophysical model that the deep leucogranites and the host rocks of the Be‐W‐Sn ore bodies can be well identified. Their morphologies and locations play a significant role for rare metal prospecting.