Evolution of the Kangmar Dome, southern Tibet: Structural, petrologic, and thermochronologic constraints

The Malashan metamorphic complex in southern Tibet: Dominantly top-to-the north deformation and intrusive origin of its associated granites

“…In addition, D2 foliation is, on the whole, most strongly developed in the region adjacent to the granite bodies and becomes less strongly developed with increasing distance from the granite bodies. These features are strikingly similar to those of D2 recognized for the Kangmar dome (Chen et al 1990, Lee et al 2000.…”

“…However, this deformation has not been well-documented. Even for the Kangmar dome (Figure 1), the most accessible and well-documented metamorphic dome, two contrasting views exist about the kinematic nature of the associated deformation: (i) dominantly top-to-the north shear (Chen et al 1990); and (ii) bulk pure shear reflected by a combination of top-to the north and top-to the south senses of shear in the northern and the southern parts of the dome, respectively (Lee et al 2000). A second important point to be assessed is the origin of the granitic cores to the metamorphic domes.…”

“…A second important point to be assessed is the origin of the granitic cores to the metamorphic domes. In the Kangmar dome the granite is thought to represent part of the basement root complex and not an intrusion during the Himalayan orogeny (Chen et al 1990, Lee et al 2000. To obtain new insights into these issues and to compare our new results with the Kangmar examples, structural and geochemical studies were carried in a metamorphosed region of Malashan area, located about 400 km west of the Kangmar dome (Figure 1).…”

Crustal–lithospheric structure and continental extrusion of Tibet

“…The South Tibetan Detachment faults form the passive roof fault of the southward extruding Greater Himalayan Sequence partially molten mid-crust during the Early Miocene (c. 23-15 Ma). The South Tibetan Detachment faults have a cumulative geological offset of c. 100 km or more and link north with the folded normal fault detachments that bound the tops of the North Himalayan domes (Lee et al 2000). There is no evidence that these faults are active today, although they must have been at low angles during their Miocene slip, or that they have been rotated from steeper faults (Searle 2010).…”

Thick-Skinned and Thin-Skinned Tectonics: A Global Perspective

“…This antiform has been explained by different mechanisms. [72] express the possibility that the Kangmar dome, one of the North Himalayan gneiss domes located farther east at 91°E, developed above a ramp of the Gyirong-Kangmar thrust, which was active at about 11 Ma. This thrust fault ceases to exist and is not recognized along the traverse of Figure 20; it is therefore indicated as a questionable blind thrust.…”