Palaeomagmetism of Permian rocks from Sardinia - Testing Pangaea B

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Palaeomagnetic reconstructions of the distribution of the continents during Permian times result in a significant overlap between Gondwana and Laurasia when Wegener's classical Pangaea fit (Pangaea A) is adopted. This problem can be overcome by shifting the southern continents some 3000 km towards the East, thus removing continental overlap (Pangaea B). However, since there is a general agreement that opening of the Atlantic started from a Pangaea A configuration, a major shear zone is required between Gondwana and Laurasia along which Gondwana was transferred into the Pangaea A fit prior to Jurassic times. This solution, however, has been challenged and it has been argued that the continental overlap in Pangaea A reconstructions reflects either poor data quality, inclination shallowing in sediments or the effects of zonal octupolar fields affecting the Earth Magnetic Field. The project proposed here, addresses the problem of locating the shear zone required by Pangaea B models. Palaeomagnetic studies designed to identify block rotations in Permian continental sediments and volcanics from Sardinia will ultimately lead to a better understanding of geodynamic processes during the Permian.