New Paleomagnetic Insights to the Breakup of Proterozoic Supercontinent Rodina

Paleomagnetism of Cryogenian Kitoi mafic dykes in South Siberia: Implications for Neoproterozoic paleogeography

Authors:

1. Sergei A. Pisarevsky (a, b, c)

2. Dmitry P. Gladkochub (d)

3. Konstantine M. Konstantinov (d)

4. Anatoly M. Mazukabzov (d)

5. Arkady M. Stanevich (d)

6. J. Brendan Murphy (e)

7. Jennifer A. Tait (a)

8. Tatiana V. Donskay (d)

9. Innokenty K. Konstantinov (d)

Affiliations:

a. The Grant Institute, University of Edinburgh, King's Buildings, Edinburgh EH9 3JW, UK

b. ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) and The Institute for Geoscience Research (TIGeR), Department of Applied Geology, Curtin University, GPO Box U1987, Perth, WA 6845, Australia

c. School of Earth and Environment, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia

d. Institute of the Earth's Crust, Siberian Branch of the Russian Academy of Sciences, 128 Lermontov Str., Irkutsk 664033, Russia

e. Department of Earth Sciences, St. Francis Xavier University, Antigonish NS B2G 2W5, Canada

Abstract:

We present a new paleomagnetic pole of 1.1°N, 22.4°E, A95 = 7.4° from the 760 Ma gabbro-dolerite Kitoi dykes located in the southern part of the Siberian Craton. The pole is supported by contact tests and suggests closer position of Siberia relative to Laurentia at 760 Ma than in Mesoproterozoic. We propose that this closer configuration was achieved by dextral transpressive motion of Siberia relative to Laurentia between 780 and 760 Ma. This motion was probably initiated at the first stage of the Rodinia breakup and is coeval with the 780 Ma Gunbarrel magmatic event of the western Canadian shield.