Palaeomagnetic correlation of Tunguska syneclise traps of Siberian platform with Permian-Triassic global stratotype of Zhejiang Province, Southern China

The purpose of the International Chinese-Russian Geological Expedition of students and teachers in Nanjing and the Yangtze River Delta (China) from October 26 to November 9, 2024 was to establish common connections and patterns in the geological structure and development of the Siberian and South China platforms. The group visited a number of sites of high scientific importance in order to understand the formation patterns of the modern appearance of East Asia beginning from the Late Permian-Early Triassic period (about 250 million years ago). Based on palaeomagnetic data, it was revealed that at the Permian-Triassic boundary these lithospheric blocks were located more than 1,500 km apart separated by the Mongol-Okhotsk Ocean, which closed at the end of the Early Cretaceous period (about 125 million years ago). That was the time when Siberian platform featured active tectonic and magmatic processes related to the Tunguska syneclise trap formation while calm sedimentation of terrigenous-sedimentary strata in marine conditions took place on the South China platform. These geological processes have become the main objects of the research presented in the article. The methodology consisted of collecting and analyzing quantitative data indicating the synchronicity of specified events in time, which will find application in solving a wide range of geological problems including interregional correlations of stratigraphic sections, tectonic-magmatic processes, study of catastrophic phenomena, etc. Materials from paleontological, isotopic, paleomagnetic and other studies (authors’ and published by other researchers) were used as a factual basis. The conducted research has shown that the deposition time of the Katangsky volcanic complex basites of the Tunguska syneclise corresponds to the Permian-Triassic boundary of the Meishan section D (Changxing District, Zhejiang Province, South China).