RUSSIAN JOURNAL OF EARTH SCIENCES VOL. 8, ES1002, doi:10.2205/2005ES000185, 2006

European Permian-Triassic Paleomagnetic Pole

[45]  At the present time there is a sufficiently large number of paleomagnetic determinations for "Stable" Europe. However not all of them satisfy the requirements imposed on the quality of paleomagnetic data. Recently Van der Voo and Torsvik [2004] carried out a meticulous selection of the paleomagnetic data available for "Stable" Europe and calculated the mean paleomagnetic poles for the time interval of 40-300 Ma, using different criteria, such as, the dating quality and the intensity of magnetic cleaning (DC). In this paper we use the poles of "Stable" Europe with a DC parameter larger than or equal to 3, and were obtained for Late Permian of Early Triassic rocks, the average ages of which correspond to the time interval of 240-260 Ma.

[46]  We added 3 poles to the poles suggested by R. Van der Voo and T. H. Torsvik, one of them being published recently [Szurlies et al., 2003]. As follows from the World Database [Pisarevsky and McElhinny, 2003], the poles suggested by Biquand [1977] and by Rother [1971] have DC=3 rather than 2, as suggested by Van der Voo and Torsvik [2004]. Moreover, the Rother pole reported by Van der Voo and Torsvik [2004] is dated as a Scythian-Ladinian one (227-250 Ma), whereas in the Database its age interval is given as 241-245 Ma.

[47]  Also discussed in this paper is the pole obtained for the Esterel igneous, including effusive, rocks [Zijderveld, 1975], dated Saxonian by Van der Voo and Torsvik [2004]. Van der Voo and Torsvik [2004], although in the Global Paleomagnetic Database these rocks are suggested to be 245-256 Ma old. We prefer to date these rocks Saxonian (258-270 Ma) because their host rocks are Saxonian [Zijderveld, 1975].

[48]  We did not use the Permian-Triassic poles obtained for the eastern part of the East European platform [Boronin et al., 1971; Burov, 1979; Iosifidi et al., 2005; Khramov, 1963] for the following two reasons. One of them is the fact that the more notable difference between the compared average poles (if any) calls for the use of paleomagnetic data from the areas located at maximum distances from one another in the inferred rigid continental block. Consequently, the poles obtained for the westernmost part of the North Asian craton are more preferable than the poles obtained for the eastern part of the Russian Platform.

[49]  The second reason stems from the fact that all of the poles available for the eastern part of the Russian platform show DC values lower than 3 and, hence, do not satisfy the adopted criteria of data selection. The pole recently reported by Gialanella et al. [1997] satisfies the quality criteria, yet, being only one pole available, cannot be used in statistical calculations. Moreover, its position differs markedly from the positions of the other Permian-Triassic poles of the Russian Platform [Iosifidi et al., 2005], this point calling for a special discussion which is beyond the scope of this paper.

[50]  Table 3 offers two versions of an average European Permian-Triassic pole. One of them was calculated using the data sample offered by Van der Voo and Torsvik [2004], the other being based on a larger data sample offered in this paper (see above). Like in the case of Siberia, both of the calculated poles are located in the vicinity of each other and do not show any statistical difference ( g/g c = 2.1/7.8).

[51]  It is important to note that most of the European paleomagnetic determinations were made using sedimentary rocks.


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Citation: Veselovskiy, R. V., and V. E. Pavlov (2006), New paleomagnetic data for the Permian-Triassic Trap rocks of Siberia and the problem of a non-dipole geomagnetic field at the Paleozoic-Mesozoic boundary, Russ. J. Earth Sci., 8, ES1002, doi:10.2205/2005ES000185.

Copyright 2006 by the Russian Journal of Earth Sciences

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