Palaeomagnetism of Palaeozoic rocks from the Cabo de Penas, Asturia, Spain

Ordovician volcanic samples of the Cabo de Penas area yielded a primary remanent magnetization (D=202°, I=78°, α95=6°) which is partially or entirely overprinted by a Late Palaeozoic remagnetization. Late Devonian-Early Carboniferous sedimentary samples reveal a pre- or syntectonic Carboniferous remanent magnetization similar to the secondary one of the volcanic samples. A soft post-tectonic component appears also in few samples, for which a Late Carboniferous age is inferred. Comparison of the Carboniferous remanent magnetizations and structural parameters suggests that in a late stage of the deformation, the sites have undergone minor rotations around a vertical axis. A ‘strike correction’ is therefore proposed to take such an effect into account. The average of the corrected mean-site directions (D=178°, I=19°, α95=9°) is considered to be a good approximation of the Early or Middle Carboniferous palaeomagnetic direction in Asturia.