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To better understand the India-Asia collisional process and intracontinental deformation within Asia, a paleomagnetic study has been conducted on the Qushenla Formation lava flows dated at~132-120 Ma from the Yanhu area in the western Lhasa terrane. Stepwise thermal demagnetization isolates stable characteristic remanent magnetizations, which include dual polarity and pass fold tests at a 99% confidence level, indicating primary magnetizations. The tilt-corrected site-mean direction for 51 sites is D = 28.2°, I = 34.5°, and k = 74.3°w ith α 95 = 2.3°, corresponding to a paleopole at 61. 4°N, 192.9°E (A 95 = 2.1°). Our new paleomagnetic data, combined with previous Cretaceous volcanic paleomagnetic data from the Lhasa terrane, show that the precollisional southern margin of Asia was at~16.8°N with a relatively E-W alignment and that the Lhasa terrane did not experience significantly discrepant north-south movement although local vertical axis rotations did take place after the Cretaceous. Comparison with the apparent polar wander paths (APWPs) of India and the Cretaceous-Paleocene paleopoles of the Tethyan Himalaya shows that the India-Asia collision was at~54.3 Ma and the Greater India during the Paleocene had a large northern extent of~2000 km (~18.1°) beyond its present northern margin. Comparison with the Cretaceous Eurasian APWP indicates that a latitudinal convergence of~1000 km has taken place between the Lhasa terrane and Eurasia since the India-Asia collision. The amount of north-south shortening deduced from Cretaceous paleomagnetic data is consistent with that accommodated by the Cenozoic fold and thrust belts between the Lhasa terrane and the Hexi corridor.

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To better understand the Neotethyan paleogeography, a paleomagnetic and geochronological study has been performed on the Early Cretaceous Sangxiu Formation lava flows, which were dated from ~135.1 Ma to ~124.4 Ma, in the Tethyan Himalaya. The tilt-corrected site-mean characteristic remanent magnetization (ChRM) direction for 26 sites is Ds = 296.1°, Is = −65.7°, ks = 51.7, α95 = 4.0°, corresponding to a paleopole at 5.9°S, 308.0°E with A95 = 6.1°. Positive fold and reversal tests prove that the ChRM directions are prefolding primary magnetizations. These results, together with reliable Cretaceous-Paleocene paleomagnetic data observed from the Tethyan Himalaya and the Lhasa terrane, as well as the paleolatitude evolution indicated by the apparent polar wander paths (APWPs) of India, reveal that the Tethyan Himalaya was a part of Greater India during the Early Cretaceous (135.1–124.4 Ma) when the Neotethyan Ocean was up to ~6900 km, it rifted from India sometime after ~130 Ma, and that the India-Asia collision should be a dual-collision process including the first Tethyan Himalaya-Lhasa terrane collision at ~54.9 Ma and the final India-Tethyan Himalaya collision at ~36.7 Ma.

To better constrain the origin and drift history of the North Qiangtang terrane (NQT), we report a well‐dated paleomagnetic pole from the Late Permian volcanics of the NQT that appears to average out secular variation. Our new results yield a paleolatitude of −7.6 ± 5.6°N at ~259 Ma for our sampling area, which confirms the NQT drifted northward during the Permian and Triassic periods. The equatorial paleolatitude of the NQT is similar to that of the coeval South China block, demonstrating that they were in close proximity. Combined with palaeontological and magmatic evidence, paleomagnetic constraints on the drift of the NQT in the Permian indicate that the NQT moved northward together with the South China block at this time. The paleolatitude evolution of the NQT implies that the NQT rifted from the northern margin of the Gondwana in the Devonian, which is earlier than the departure time of the South Qiangtang terrane.