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Recent studies highlight the debates about the role of the northwestern China blocks, for example, north Tarim block, south Tarim block (STB), Altyn Tagh block (ATB) and Qaidam‐Qilian block (QQB) during the assembly of Rodinia. We herein present a combined paleomagnetic, geochronological, and geochemical study on 16 mafic dikes in the northern ATB. After removing a recent viscous remanent magnetization, three characteristic remanent magnetization components (CHs) were isolated. CH1 was identified in eight NW‐trending diabase dikes, one of which was newly dated at 895.3 ± 7.7 Ma through use of SHRIMP baddeleyite U‐Pb methodology. It yields a mean direction (D/I) of 123.3°/−42.2° (α95 = 12.1°). The paleopole (40.9°S/184.6°E, A95 = 11.7°) was calculated by averaging eight virtual geomagnetic poles (VGPs) from each dike. A partial baked‐contact test supports the primary origin of CH1. CH2 was isolated from three E‐W trending diabase dikes, pointing northwest with considerably shallower downward inclinations. CH3 was obtained from five lamprophyre dikes, directing southeast with moderate to shallow upward inclinations. However, the VGPs of either CH2 or CH3 are insufficient to average a precise mean pole. Geochemical analyses also reveal petrogenetic discrepancy among the dikes with distinct CHs. Combining the new ∼895 Ma pole of CH1 with the global paleomagnetic database and being aided by geological evidence, we propose that the STB‐ATB‐QQB and the north China craton were located along the northwestern side of Laurentia in Rodinia at ∼895 Ma, and suggest the connection might have been intact until ∼780 Ma. Plain Language Summary: The paleogeographic positions of the northwestern China blocks, including the north Tarim block, the south Tarim block, the Altyn Tagh block (ATB) and the Qaidam‐Qilian block in the Rodinia supercontinent, remain enigmatic and highly controversial. Here we present new paleomagnetic geochronological and geochemical data from three groups of the mafic dikes in the northern ATB. Our new results, in combination with other coeval paleomagnetic poles and geological evidence, support a specific proximity among the south Tarim, Altyn Tagh, Qaidam‐Qilian blocks and the north China craton along the northwestern side of Laurentia between ∼895 and ∼780 Ma. Key Points: A new paleomagnetic pole was obtained from eight early Neoproterozoic mafic dikes in the northern Altyn Tagh blockThe pole was dated at 895.3 ± 7.7 Ma using baddeleyite U‐Pb SHRIMP methodologyThe adjacent south Tarim‐Altyn Tagh‐Qaidam‐Qilian block and north China craton were located at NW side of Laurentia on the periphery of Rodinia [ABSTRACT FROM AUTHOR]

• U-Pb ages of ~801.9 Ma and ~804.6 Ma were got from the Madiyi Formation, South China. • A ~800 Ma paleopole was reported from the Madiyi Formation. • South China was at a high latitudinal position at ~800 Ma. • South China was unlikely to be in the central position of Rodinia at ~800 Ma. New geochronological and palaeomagnetic data are presented for the Madiyi Formation of the lower Banxi Group in the South China Block (SCB). Zircon U–Pb dating of two tuff beds within the sampled section yielded consistent ages of 801.9 ± 6.3 Ma and 804.6 ± 9.6 Ma. A total of 137 palaeomagnetic samples were collected and thermally stepwise demagnetized. Three components were isolated. Component A was identified in 30 samples below 300 °C. It has a mean direction resembling the recent geomagnetic field, and is interpreted of recent viscous remanent magnetization. Component B, typically isolated below ~660 °C, yields a pole in situ close to the Cretaceous poles of the SCB and is interpreted as a Cretaceous overprint. Component C was identified in 90 samples, determined in the high-temperature steps between 660 and 690 °C. It yielded a mean direction of Ds = 293.1°, Is = 69.9° (k = 22.3, α 95 = 3.2°) after tilt correction, corresponding to a palaeopole of 35.3°N, 67.9°E (dp = 5.5°, dm = 4.7°) and palaeolatitude of 53.8 +4.9/−4.7°N for the study area. Inclination correction using an empirical flattening factor f = 0.6 yielded a corrected mean direction of Ds* = 293.0°, Is* = 77.3° (k = 51.4, α 95 = 2.1°), corresponding to a palaeopole of 34.3°N, 82.4°E (dp = 3.9°, dm = 3.7°) and palaeolatitude of 65.7 +3.7/−3.6°. Component C records five polarity zones and passes a reversal test. The pole diverges from all younger poles of the SCB, and is interpreted to be of primary remanent magnetization. Our results reveal a high-latitude position of the SCB at ~800 Ma. Comparing with other two poles from the Xiaofeng dykes (~821 Ma) and Yanbian dykes (~824 Ma) reveals no significant latitudinal difference for the SCB between ~820 and 800 Ma. However, coeval poles from the global palaeomagnetic database, along with geological evidence, indicate that East Svalbard, Australia and Laurentia were located around the equator at ~800 Ma. The striking difference in palaeolatitude suggests that the SCB was unlikely to be located between southeastern Australia and western Laurentia in the Rodinia supercontinent at ~800 Ma. [ABSTRACT FROM AUTHOR]