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Siberian Apparent Polar Wander Path for the Eon: towards finding Siberian Place on D. Blanco 1, V.A. Kravchinsky 1, K. Kabin2 1Physics Department, University of Alberta, Edmonton, AB, Canada email: [email protected] 2 Physics Department, Royal Military College of Canada, Kingston, ON, Canada

Abstract Presentation Number1180456 Kuzmin et al. (2010) Work in Progress Introduction Smirnov and Tarduno (2010) The existence of as an independent stable platform can be traced back with accuracy from the breakup of 180 180 Figure 2 (~800 Ma) until the end of the Paleozoic Eon when it became part of . Different continental blocks 248 Ma 295 295 A B 291 250 Ma Comparison between European APWPs constructed Present accreted to Siberia since Precambrian forming one of the largest tectonic structures on Earth – Siberian . 283 300 283 300 228 Ma 275 275 278 278 with the SVD least squares method using different At the same time Siberian apparent polar wander path (APWP), which is crucial for global tectonic reconstructions, 296 296 300 300 number of polynomials m (A) and the smoothing 360 Ma 348 Ma still contain long unresolved segments. 242 242 method using different smoothing parameters S Kuzmin et al. (2010) 267 Torsvik et al. 2001 267 Torsvik et al. 2001 o o o 45 75

(B). The 95% confidence circles are not shown for 15 267 209 267 209 In this contribution, we present the behavior of two fitting methods (a least-squares fit computed through singular 201 221 221 clarity. Red path with crosses is the APWP of African 198 198 S=35 m=10 value decomposition (SVD) and a smoothing technique) when applied to extensive and sparse data sets. During the S= 15 157 m=6 LLSVP 448 Ma 159 157 from Torsvik et al. (2001) (their Table 2). In- 168 159 168 140 216 209 140 209 Mesozoic Era we considered two possible scenarios discussed in the literature: Siberia was regarded as a consolida- 157 157 216 dividual paleomagnetic poles from Table 1b of Tors- 192 201 192 201 158 158 ted component of Eurasia since Triassic (Cocks and Torsvik, 2007); and Siberia was an independent continent 201 179 179 201 vik et al. (2001) are shown as green points. (Metelkin et al., 2010)). Furthermore, we follow Kuzmin et al. (2010) and Smirnov and Tarduno (2010), who recons- 184 184 90 548 Ma 198 198 tructed the paleoposition of Siberian platform with respect to the present day Icelandic hot spot, in order to perform Figure 5 an absolute tectonic reconstruction of the Siberian continent during the Phanerozoic. Location of Siberian continent during 250 Ma (purple dot) and 360 Ma (green star), as

250 Ma 250 Ma proposed by Kuzmin et al. (2010). The African LLSVP is demarcated by the red dashed 250 Ma line. We will perform an absolute reconstruction of the position of Siberia using our 228 Ma 228 Ma S=30 APWP (black dots) during the Paleozoic taking as a reference point the Icelandic posi- 228 Ma B m=6 tion of Siberia during the Permo-Triassic boundary. Taymir Fold Belt A 70 o 250 250 Cocks and Torvik, 2007 446 Ma 446 Ma Enisey-Khatanga aulacogen Verkhoyansk 200 248 248 250 200 250 Omolon, 275 275 Kolyma and 446 Ma surrounded 228 228 blocks

Fold Belt 538.5 Ma 538.5 Ma Conclusion

Ob aulacogen Siberian 365 365 An updated apparent polar wander path of Siberia along the Phanerozoic Eon is presented. o 538.5 Ma 60 445.5 519 Ma 519 Ma platform 445.5 Two techniques to fit curves to the paleomagnetic pole have been tested on the extensive 464 464.5 444.5 444.5 464.5 519 Ma data set of Europe and on the sparse data set of Siberia. The least-squares fit computed 424 424 o 500.5 100 N 448.5 448.5 468 Belt 494.5 478 Siberia and Metelkin

o A through singular value decomposition (SVD) presents smooth paths and provide a good fit West Siberian basin 464 Siberia and Europe 483.5 538.5 483.5 538.5 Sayan Fold 494.5 505.5 o 50 o N 480 80 N to the general tendency of the paths. The smoothing method is more sensitive to the fea- Belt 507 524 Fold 524 470 SVD Method 60 o N 519 507 519 o o 480 483.5 Smooth Method 483.5 tures (cusps) and presents a less smooth fitting to the data. 50 Fold o Altay Fold Belt Baikal 40 o N 0 494.5 Latitudinal Drift ( ) Relative tectonic reconstructions are presented using the Siberian data sets including Metel- TMn 20 o N Figure 1 50 o S Belt Mongol - Okhotsk 0o 40 100 150 200 250 300 350 400 450 500 kin et al. (2010) poles and European poles during the Mesozoic. Both paths demostrate Amuria Latitudinal Drift ( ) 35 Left hand side: Simplified geological structure of Siberia and surrounding 20 o S B Geological Time (Ma) Jun 30 ? similar latitudinal displacements and APWP migration velocities. o 40 S 25 modified from Kravchinsky et al. (2002). 1: Precambrian shields; 250 300 350 400 450 500 550 Geological Time (Ma) 20 Absolute tectonic reconstructions are still being developed and will be completed taking o 2: Riphean and Palaeozoic sediment cover; 3: Permo-Triassic traps; 15 40 Tarim into account the location of Siberia above the Icelandic hotspot at 250 Ma and above the North China Figure 3 10

4: Viluy palaeorift; 5: edge of Precambrian platform; 6: Middle–Late APWP velocity (cm/year) Block 5 African LLSVP during the Paleozoic. Up: Comparison between Siberian APW paths 0 Palaeozoic border of Siberian block. Names of blocks: TMn: Tuva-Mongolian, 100 150 200 250 300 350 400 450 500 550 Qiangtang for 228-550 Myr interval constructed with Sibe- Figure 4 Geological Time (Ma) o Jun: Jungar ; 7: paleomagnetic study sampling localities. 100 110 o 120o rian dataset. Green squares: smooth method Up: Left, APWP construted with SVD least squares References Cocks, L. R.M., Torsvik, T.H., 2007. Siberia, The wandering northern terrane, and its changing geography through the Paleozoic. Earth- 1 2 3 4 with S=30. Blue diamonds: SVD least squares method, m=10. Rigth, APWP constructed with Right hand side: Selected paleomagnetic poles with 95% confidence ovals Science Reviews, 82, 29–74. with m=6. Red cross: APWP of Cocks and Torsvik smoothing method, S=30. Comparison paths includ- Gurevitch, E.L., 1984. Palaeomagnetism of the deposits of the Moyero River sequence. Palaeomagnetic Methods in Stra- 6 7 for the Siberian APWP construction. Following Gurevitch (1984) and Pavlov 5 (2007). The 95% confidence circles for the APWP ing Metelkin et al. (2010) Siberian poles vs. Euro- tigraphy. VNIGR, St Petersburg, pp. 35–41 (In Russian). and Petrov (1996), the poles from 407 to 430 Ma have been rotate to take Kravchinsky, V.A., Konstantinov, K.M., Cogné, J.-P., 2001. Palaeomagnetic study of Vendian and Early rocks of South Siberia are not shown for clarity. Individual Siberian pean poles from Torsvik et al. (2001) during the Me- into account the opening of the Viljuy Basin. Plot A represents the selected and Central Mongolia: was the Siberian platform assembled at this time? Precambrian Research 110, 61–92. poles and their 95% confidence circles are sozoic is shown. Blue squares/diamonds: Metelkin’s Kuzmin, M.I., Yarmolyuk, V.V., Kravchinsky, V.A., 2010. Phanerozoic hot spot traces and paleographic reconstructions of the Siberian poles without rotation. Plot B, corrected poles respect an Euler pole of continent based on interaction with the African large low shear velocity province. Earth-Science Reviews, 102, 29–59. shown as circles. A 20 Ma windows was used for poles and Siberian poles; purple triangles: European latitude 60°N, longitude 120°E and angle of 13° (Cocks and Torsvik, 2007). Metelkin, D.V., Vernikovsky, V.A., Kazansky, A.Y., Wingate, M.T.D., 2010. Late Mesozoic tectonics of Central based on paleomag- the APWP construction. and Siberian poles. netic evidence. Research, 18, 400–419. o o Pavlov, V.E., Petrov, P.Y., 1996. Paleomagnetic investigation of the Riphean sediments of the Turukan . Fizika Zemli 3, 71–81 (In Down: Latitudinal drift for a reference point at Down: A: Latitudinal drift for a reference point at 65 N Russian). 65 N and 105 E, based on SVD least squares and and 105 E. B: APWP migration velocity. Both plots where Smirnov, A.V., Tarduno, J.A., 2010. Co-location of eruption sites of the and North Atlantic ignous province: Implications for the nature of hotsptos and mantle plumes. Earth and Planetary Science Letters, 297, 687-690. smooth paths. based on SVD least squares with m=10. Torsvik, T.H., Van der Voo, R., Meert, J.G., Mosar, J., Walderhaug, H.J., 2001. Reconstructions of the around the North Atlan- tic at about the 60th parallel. Earth and Planetary Science Letters, 187, 55–69.