The Apparent Polar Wander Path of the Tarim block (NW China) since the Neoproterozoic and its implications for a long-term Tarim-Australia connection

In order to better understand the kinematic history of the Tarim block after the breakup of the Rodinia supercontinent, paleomagnetic studies have been carried out on Neoproterozoic strata from the Quruqtagh and Yecheng areas in the northeastern and southwestern Tarim block (NW China), respectively. Totally, 547 sedimentary and volcanic samples were collected from 64 sites. Magnetic mineralogical studies show that titanium-poor magnetite and hematite are the principal magnetic remanent carriers. For the Quruqtagh area, the directional analyses reveal that the stable and primary magnetic remanences have been isolated from the ca. 635 Ma Tereeken Formation cap carbonate and the 615 Ma Zhamoketi basaltic andesite, providing two Neoproterozoic paleomagnetic poles at: lambda = 27.6 degrees N, j)= 140.4 degrees E, dp = 8.8 degrees, dm = 11.1 degrees for the Tereeken Formation and lambda = -4.9 degrees N, j = 146.7 degrees E, dp = 3.0 degrees, dm = 5.2 degrees for the Zhamoketi formation. Nevertheless, all other Neoproterozoic formations from this area show magnetic directions close to either the Present Earth Field (PEF) or the Late Carboniferous-Early Permian ones. Samples from the Yecheng area yield high anisotropy degree values and near vertical magnetic fabrics indicating the absence of reliable Neoproterozoic magnetic remanence. Combined these two newly obtained paleomagnetic poles with the previously published ones, an Apparent Polar Wander Path (APWP) from the Neoproterozoic to the Present has been built for the Tarim block. The comparison between the APWPs of Tarim and Australia implies a long-term Australia-Tarim connection and/or same kinematic evolution from at least the Neoproterozoic until the Middle Silurian. The Tarim block probably began to break away from northwestern Australia since the Late Ordovician and the final separation occurred at the Late Silurian-Early Devonian. (C) 2014 Elsevier B.V. All rights reserved.