New Paleomagnetic Insights Into the Neoproterozoic Connection Between South China and India and Their Position in Rodinia

• Published in: Geophysical research letters 2022-05, Vol.49 (10), p.n/a
• Main Authors: Chang, Linxi, Zhang, Shihong, Li, Haiyan, Xian, Hanbiao, Wu, Huaichun, Yang, Tianshui
• Format: Article
• Language: English
• Subjects: Cratons; Field tests; Geological data; Geology; India; Latitude; Linkages; Magnetism; Neoproterozoic; Palaeomagnetism; Paleomagnetism; Poles; Quality assurance; Reconstruction; Sills; south China; Tectonics
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2022GL098348

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 China South China was connected to India via Indochina and small Asian blocks at ca. 770 Ma The South China‐India landmass was located at high‐to‐mid latitudes and far away from the core of Rodinia at ca. 770 Ma