Eclogite and blueschist are important monitors of subduction zone processes and can record complex polymetamorphic histories during the protracted evolution of subduction systems. However, the rarity of such high-pressure, low-temperature metamorphic rocks in the Indus-Yarlung suture zone of the Himalaya hinders our understanding of the convergence of India and Asia. Here, we examine high-pressure, low-temperature metamorphic rocks from the Milin area of the eastern Indus-Yarlung suture zone. A comprehensive microtextural, mineral chemistry, and phase-equilibrium modeling investigation shows that low-temperature eclogite-facies metapelites with different parageneses (garnet-mica schists) experienced a cold subduction history along a low-thermal gradient, with peak pressures of ∼1.6 GPa at ∼550 °C. This represents an approximate thermal gradient of ∼10 °C km−1. After peak pressure, these rocks underwent a two-step exhumation history with initial exhumation accompanying heating at ∼590−600 °C and ∼0.8−1.0 Gpa; this was followed by the second stage of exhumation to lower amphibolite-facies conditions. We interpret these low-temperature eclogite-facies metapelites to represent sedimentary rocks that overlaid Neo-Tethyan oceanic crust during subduction. Exhumation paths of high-pressure, low-temperature rocks in the eastern Indus-Yarlung suture zone include an amphibolite-facies overprint, which is absent from high-pressure, low-temperature rocks in the western Indus-Yarlung suture zone. This result is caused by the different timing of exhumation relative to the terminal collision of India and Asia.

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