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The identification of the Grenvillian‐age ophiolite suites in the Yangtze block in recent years suggested that the northern Yangtze subblock (NYB) and the southern Yangtze subblock (SYB) were once separated by an ocean in late Mesoproterozoic. Although some paleogeographic models advocated the Pre‐Grenvillian connections between the south China blocks and Laurentia, none of them has been paleomagnetically tested. Here we report the new paleomagnetic results obtained from the ∼1,270 Ma purplish‐red muddy dolomite beds of the Luanshigou Formation, Shennongjia Group, NYB, providing new constraints for reconstructing the paleogeographic positions of the south China blocks in late Mesoproterozoic. A total of 447 samples underwent stepwise thermal demagnetization. Two components were identified. The low‐temperature component is interpreted as the recent viscous remnant magnetization. The high‐temperature component was obtained from 64 samples below 580°C and from 177 samples below 690°C, directed northeast‐up or southwest‐down, antipodally, positioning the paleomagnetic pole at 18.5°S, 74.4°E (dm/dp = 2.5/1.6°). Rock magnetic results demonstrate that the magnetic carriers in purplish‐red dolomite and pale‐pink dolomite are predominated by hematite and magnetite, respectively. The data quality is supported by an inverse baked contact test, a B‐class reversal test, and the paleomagnetic pole is distinct from any younger poles of the region. Based on the paleomagnetic results, aided by geological evidence, we propose a reconstruction in which the NYB was juxtaposed to southwestern Laurentia in the late Mesoproterozoic and suggest that the late Mesoproterozoic Miaowan‐Shimian ophiolite zone in the Yangtze block was likely an extension of the Grenville belt of Laurentia. Plain Language Summary: The south China block was traditionally subdivided into the Yangtze block to the northwest and the Cathaysia block to the southeast, which were separated by an early Neoproterozoic ocean. Recently published geological data further suggest that the Yangtze block contains two subblocks, the NYB and the SYB, which were separated by a late Mesoproterozoic ocean. Several paleogeographic models proposed the Mesoproterozoic relationships between the south China blocks and Laurentia, but none has been paleomagnetically tested. Here we report a new paleomagnetic pole obtained from the ∼1,270 Ma purplish‐red dolomite beds of the Luanshigou Formation, Shennongjia Group in the NYB. The data quality is assured by the positive paleomagnetic field tests. Our results combing with the geological evidence suggest that the NYB was located in a low‐latitudinal position and connected to southwestern Laurentia in the late Mesoproterozoic. The late Mesoproterozoic ophiolite zone in the southern margin of the NYB was likely an extension of the Grenville belt. Key Points: A new paleomagnetic pole (18.5°S, 74.4°E, dm/dp = 2.5/1.6°) was obtained from the late Mesoproterozoic Luanshigou Formation of the Shennongjia Group in south ChinaThe northern Yangtze subblock (NYB) was connected to southwestern Laurentia at the late MesoproterozoicThe late Mesoproterozoic Miaowan‐Shimian suture zone in the southern margin of the NYB was likely an extension of the Grenvillian orogenic belt [ABSTRACT FROM AUTHOR]

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]

A paleogeographic affinity of the south China craton (SCC) with India in the Neoproterozoic has long been advocated based on lines of geological evidence. However, the lack of coeval paleomagnetic data renders the putative connection ambiguous. Here we report new paleomagnetic results obtained from seven ca. 770 Ma mafic sills in SCC that provide new critical constraints on the issue. The data quality is assured by a positive regional tilt test, a reversal test, and by adequately averaging‐out paleosecular variation. Our data, together with coeval poles from the global paleomagnetic database, support a reconstruction in which the SCC was connected with India at ca. 770 Ma via linkages with smaller continental blocks. The SCC‐India landmass was located at high‐to‐mid latitudes and far from Laurentia and Australia, which were located at low latitudes at ca. 770 Ma. Plain Language Summary: Multiple lines of geological evidence may suggest a close paleogeographic relationship between the south China craton (SCC) and India. Their specific connection, including the alignment of tectonic features, if had ever existed in any way, can be tested and determined through the use of coeval high‐quality paleomagnetic data from the two cratons. In this paper, we report a new paleomagnetic pole obtained from seven ca. 770 Ma mafic sills in the SCC, which is coeval to the pole obtained from the Malani igneous suite in India. The data quality of both poles is assured by robust paleomagnetic field tests. Our reconstruction based on the updated paleomagnetic database and geological data demonstrates that the SCC was connected with India at ca. 770 Ma via linkages with other smaller Asian blocks. Furthermore, the SCC‐India landmass was located at high‐to‐mid latitudes and far from the core of Rodinia, for example, Laurentia and Australia, which were located at low latitudes at ca. 770 Ma. Key Points: A new paleomagnetic pole (25.6°N, 116.8°E, A95 = 9.9°) was obtained from ca. 770 Ma mafic sills in South ChinaSouth China was connected to India via Indochina and small Asian blocks at ca. 770 MaThe South China‐India landmass was located at high‐to‐mid latitudes and far away from the core of Rodinia at ca. 770 Ma [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]