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The article discusses the phenomena of gneiss dome formation in the Pamir Mountains in Central Asia. It notes that unlike the Tibetan plateau, high-grade metamorphic rocks are widely exposed in at least seven gneiss domes in the Pamir, several of were said to share similar exhumation histories, indicating that they were formed through a single mechanism. Dome formation was attributed to overall transpressional thickening with long-wavelength-low-amplitude buckling of the entire crust.

Abstract: Multiple high-grade crystalline domes across the Pamir contain Barrovian facies-series metapelites with peak metamorphic assemblages of garnet+kyanite±staurolite+biotite+oligoclase±K-white mica. Thermobarometry yields pressures of 6.5–8.2kbar and temperatures of 600–650°C for the Kurgovat dome in the northwestern Pamir, 9.4kbar and 588°C for the west-central Yazgulom dome, 9.1–11.7kbar and 700–800°C for the east-central Muskol dome, and 6.5–14.6kbar and 700–800°C for the giant Shakhdara dome in the southwestern Pamir. These new data indicate exhumation of the Pamir crystalline domes from crustal depths of ~30–40km. New titanite, monazite and zircon geochronology, in conjunction with published ages, illustrate that this metamorphism is Oligocene–Miocene in all but the Kurgovat dome (where it is Triassic). If the Pamir had a pre-collisional crustal thickness less than 30km and if the India–Asia convergence within the Pamir is less than 600km, the current 70km-thick crust could have been created by plane strain with no net gain or loss of material. Alternatively, if the pre-collisional crustal thickness was greater than 30km or India–Asia convergence within the Pamir is more than 600km, significant loss of continental crust must have occurred by subhorizontal extrusion, erosion, or recycling into the mantle. Crustal recycling is the most likely, based on deep seismicity and Miocene deep crustal xenoliths. [Copyright &y& Elsevier]