Defining the main Paleo-Tethys suture in Tibet: First Permian paleomagnetic insights from the Eastern Kunlun Range

• Tuffs in Eastern Kunlun were dated to ca. 265–251 Ma using the zircon U-Pb method. • A paleolatitude of ∼27.4 ± 3.1°N was obtained for Eastern Kunlun at the Late Permian. • Jinsha suture marks the main Paleo-Tethys Ocean, closed by the Late Triassic. The location and timing of the final closure of the main Paleo-Tethys Ocean remain debated, particularly in central Tibet, where multiple suture zones have been proposed as remnants of this main oceanic basin. Here we present new zircon U-Pb geochronology and the first high-quality Late Permian paleomagnetic data from volcaniclastic rocks of the Eastern Kunlun Range, Northern Tibet. Six dated tuff samples yield emplacement ages of ca . 265–251 Ma, thus constraining the depositional age of the studied strata. Characteristic remanent magnetizations of 39 sites pass fold, reversal, and baked contact tests, indicating preservation of a primary magnetization. The tilt-corrected site-mean direction yields a paleolatitude of 27.4° ± 3.1°N at 36.1°N, 94.9°E. When combined with coeval paleomagnetic data from the Eastern Qiangtang blocks, these results imply that the Jinsha suture was the remnant of the principal Paleo-Tethys Ocean, which had a latitudinal width of ∼3,700 km during the Late Permian. The progressive convergence between the Eastern Qiangtang and Eastern Kunlun–Qaidam continent from ∼251 to 225 Ma is followed by a decline in northward plate motion, with paleolatitudinal overlap by the Late Triassic. This timing is corroborated by geological evidence including ophiolite ages, high-pressure metamorphism, magmatism, and foreland basin sedimentation. These findings provide critical paleogeographic constraints for understanding the tectonic assembly of the Tibetan Plateau and the geodynamic evolution of the Paleo-Tethyan realm.