Geochronology and petrogenesis of the early Silurian Zeluo mafic-ultramafic intrusion, eastern Tibet: implications for the tectonic setting and evolution of the eastern Proto-Tethys Ocean

The Tibetan Plateau is a key region to understand the evolution of Tethys Oceans. To better constrain tectonic Proto-Tethys Ocean on western margin Yangtze plate, we present an integrated petrography, geochemistry, and zircon U-Pb-Lu-Hf isotope study newly recognized early Silurian gabbro serpentinite rocks from eastern Yidun terrane Plateau. Zircon U-Pb dating yields Early age 438.2 ± 2.8 Ma. εHf(t) values 5.4 8.5 suggest single-stage model (TDM1) ranging 729 858 gabbros exhibit low total rare earth element abundances but are moderately enriched in light elements large-ion lithophile (e.g. Rb, Ba, Sr), display representative negative high-field strength elemental anomalies for Nb, Ta, Zr, Hf spidergrams. serpentinites were derived depleted mantle-like source made garnet-spinel lherzolite composition, sub-arc mantle wedge that was metasomatized by slab dehydration. Thus, record subduction event under plate. Furthermore, this confirms plate underlined Precambrian crystalline basement.