Discovery of Meso- to Neoproterozoic magmatism and metamorphism in the eastern Himalaya: Implications for assembly of the Rodinia supercontinent

Journal article

The Himalayan orogen formed following the Cenozoic India-Asia collision, and contains many exposures of Precambrian rocks that reveal the pre-collisional geological evolution of India and its behavior during the assembly and breakup of the Rodinia supercontinent. Here we present new geochronological and geochemical data for amphibolites and orthogneisses from the eastern Himalayan orogen, which record the first identification of Late Mesoproterozoic arc-related magmatism and Early Neoproterozoic metamorphism in the region. Magmatic zircon cores from amphibolites and orthogneisses yield mean ²⁰⁷Pb/²⁰⁶Pb ages of 1200–1140 Ma, whereas metamorphic zircon rims give mean ²⁰⁶Pb/²³⁸U ages of 940–920 Ma. These rocks have fractionated REE patterns, LILE enrichments, and negative Nb, Ta, and Ti anomalies. The amphibolites have high zircon εHf(t) values of + 2.6 to + 11.5 and whole-rock εNd(t) values of −0.80 to + 4.06, and low whole-rock ⁸⁷Sr/⁸⁶Sr_(i) ratios, while the orthogneisses have low zircon εHf(t) values of −15.1 to −0.4 and whole-rock εNd(t) values of −7.66 to −3.88, and high whole-rock ⁸⁷Sr/⁸⁶Sr_(i) ratios. These compositions suggest that the amphibolite protoliths were derived from partial melting of depleted mantle, and the orthogneiss protoliths were derived from remelting of more ancient crustal rocks during Mesoproterozoic accretionary orogeny. These records are consistent with Grenvillian tectonothermal events of the Rayner-Eastern Ghats orogen, implying that a huge Meso- to Neoproterozoic accretionary to collisional system operated along the eastern Indian margin during the assembly of Rodinia. These findings also suggest that the Lhasa terrane was situated along the northern Indian margin during the Neoproterozoic, supporting hypotheses that the Lhasa terrane previously drifted away from the Indian continent before they were combined again during the Cenozoic. These new data thus constrain Neoproterozoic plate tectonic reconstructions and paleogeographic models of Rodinia supercontinent formation.

Authors: Zhang, C; Zhang, Z; Palin, RM; Dong, X; Guo, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Precambrian Research
• Volume: 441
• Article number: 108146
• Publication date: 2026-05-14
• Acceptance date: 2026-05-09
• DOI: 10.1016/j.precamres.2026.108146
• EISSN: 1872-7433
• ISSN: 0301-9268
• Language: English
• Keywords: Himalayan orogen; Mesoproterozoic arc magmatism; Neoproterozoic metamorphism; Rodinia supercontinent; Precambrian evolution