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The interval from the late Mesoproterozoic to early Neoproterozoic is generally considered as a critical time for the amalgamation of Rodinia. The location of the North China Craton (NCC) in Rodinia remains contentious and demands greater paleomagnetic constraints. A combined geochronologic and paleomagnetic study was conducted on the late Mesoproterozoic to early Neoproterozoic rocks in the eastern NCC. Three sills were dated at ca. 945 Ma and one at ca. 920 Ma through use of the zircon U-Pb secondary ion mass spectroscopy method. Paleomagnetic investigation revealed no significant discrepancy between these sills. A positive baked-contact test, secular variation test and presence of reversals together support the primary origin interpretation for the remnant magnetization. A high-quality pole at (28.2 °S, 141.9 °E, A95 = 10.4°) was thus obtained by averaging our new results and a virtual geomagnetic pole previously reported for a ca. 920 Ma sill in the region. These Neoproterozoic sills intruded the successions that contain correlative strata that are named Nanfen, Xinxing, and Liulaobei formations in Liaoning, Jiangsu, and Anhui provinces, respectively. The Nanfen Formation and its equivalents are constrained between ca. 1120 and ca. 945 Ma by detrital zircons and the well-dated mafic sills. The paleomagnetic inclinations observed from the lower parts of the Nanfen, Xinxing, and Liulaobei formations are notably steep. The corresponding poles from these rock units are consistent and averaged at 38.6 °N, 136.7 °E (A95 = 3.2°). The quality of this pole is strengthened by a positive reversal test and its distinctiveness from the younger poles of the NCC. In the middle part of the Nanfen Formation, however, the paleomagnetic directions are characterized by moderate inclinations, being significantly different from those in the lower part of the Nanfen Formation and its equivalents. The calculated pole for the upper part of the Lower Member of the Nanfen Formation is at 8.0 °N, 128.5 °E (A95 = 7.9°). Another pole obtained from the Middle Member of the Nanfen Formation is at 11.2 °S, 127.7 °E (A95 = 8.5°). These two poles also differ from the younger poles of the NCC and likely represent the primary remanences. Our new results, together with the existing global paleomagnetic data and geological evidence, aided by the “right-way-up” connection model between Laurentia and Baltica in Rodinia, support a NCC–NW Laurentia connection between ca. 1120 and 890 Ma.

A combined paleomagnetic and geochronological study was conducted on the red beds of the Zhesi Formation (ZSF) in the Xilinhot–Songliao Block (XSB) and the andesites and sandstones of the Qingfengshan Formation (QFF) in the North China Block (NCB). The ZSF tuffs and the QFF andesites were dated to 265.3 ± 1.8 Ma and 254.8–257.1 Ma, respectively, using the zircon U–Pb laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) method. A total of 246 paleomagnetic samples were subjected to stepwise thermal demagnetization. After removal of the low‐temperature viscous components acquired in the recent geomagnetic field, stable high‐temperature components (HTCs) were isolated from most samples. The HTC of the ZSF passed a fold test, and the HTC of the QFF passed both fold and reversal tests, indicating their primary origins. The corresponding paleomagnetic poles are 57.4°N/342.0°E (A95 = 4.3°) for the XSB at ~265 Ma and 54.3°N/20.2°E (A95 = 3.3°) for the NCB at ~255 Ma. Comparison of high‐quality Permian paleomagnetic poles of the XSB and NCB reveals a latitudinal convergence and relative rotation between them that led to a scissors‐like closure of the Solonker Ocean from west to east between ~265 and ~246 Ma, which controlled the mixing of the Cathaysian and Angara floras in space and time. The XSB and NCB moved rapidly northward between ~265 and ~255 Ma, which probably accelerated the end‐Guadalupian mass extinction in East Asia.

To better constrain the evolution of the Mongol‐Okhotsk suture, we carried out new paleomagnetic studies on Sharilyn Formation (~155 Ma) and Tsagantsav Formation (~130 Ma) in southern Mongolia, Amuria Block (AMU), and Tuchengzi Formation (~140 Ma) and Dadianzi/Yixian Formation (~130 Ma) in the Yanshan belt, North China Block (NCB). A total of 719 collected samples (from 100 sites) were subjected to stepwise thermal demagnetization. After a low‐temperature component of viscous magnetic remanence acquired in the recent field was removed, the stable high‐temperature components were isolated from most samples. The high‐temperature components from each rock unit passed a fold test and a reversal test, indicating their primary origins. The corresponding paleomagnetic poles were thus calculated. For AMU, the ~155 Ma pole is at 74.7°N/232.5°E (A95 = 3.7°), the ~130 Ma pole at 74.6°N/194.7°E (A95 = 2.9°); for the NCB, the ~140 Ma pole is at 82.7°N/208.6°E (A95 = 4.3°), the ~130 Ma pole at 80.5°N/197.4°E (A95 = 2.3°). By combining our new results with the published data, we refined the 155–100 Ma segment of the apparent polar wander paths for AMU and NCB, which can demonstrate that these two blocks have been tectonically coherent (AMU‐NCB) during 155–100 Ma. Comparison of the apparent polar wander paths, however, revealed a latitudinal plate convergence of 14.3° ± 6.9° and ~19.0° relative rotation between Siberia and the AMU‐NCB after ~155 Ma. Large‐scale latitudinal convergence likely ceased by ~130 Ma, although some relative rotation between them continued along the Mongol‐Okhotsk suture until ~100 Ma.

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