New palaeomagnetic data from Argun terrane. Testing its association with Amuria and the Mongol-Okhotsk Ocean
статья в журнале
(ИНГГ СО РАН)
(ИНГГ СО РАН)
дата публикации: 2018
In this study, we present new palaeomagnetic and geological data obtained from Ediacaran and Cambrian sedimentary rocks of Argun terrane, which is traditionally considered a key element of the hypothetical Amuria composite continent. Since 1990, when Amuria was first proposed in palaeogeographic reconstructions, it became one of the principle members in the global palaeotectonic schemes. A scenario when collision of Amuria with Siberian margin resulted in formation of the Mongol-Okhotsk Ocean is universally accepted and supported by majority of researchers. However, time of Amuria's final assembly and relative position of the blocks within Amuria before the collision with Siberia is still a topic of debate. Questions about principal allocation of Argun terrane and its relation to Amuria during the late Neoroterozoic- Cambrian are addressed in this study. Palaeomagnetic poles for the Ediacaran-early Cambrian rocks of Argun terrane differ within an error from coeval poles from Siberia indicating that Argun terrane could have been located similar to its present-day positionwith respect to Siberia already at 560-525 Ma. This observation calls into question association of Argun terrane with Amuria, which in classic reconstructions is usually placed close to the North China Craton.
первоисточник: Geophysical Journal International