Implications of palaeomagnetic data from the Tortworth Silurian inlier (southern Britain) to palaeogeography and Variscan tectonism
نویسندگان
چکیده
Palaeomagnetic data are presented from early Silurian (Upper Llandovery) lavas from the Tortworth Silurian inlier of south-west England. Two magnetization components are recognized on the basis of contrasting demagnetization characteristics. A lower unblocking-temperature component (<350 "C) is oriented parallel to the Earth's present magnetic field at the sampling site (N = 46, declination = 352", inclination = 69", k = 52.1, ag5 = 2.9"). A higher unblocking-temperature component (350-600 "C) is inferred to be primary on the basis of a stratigraphy-parallel reversal pattern (combined tilt-corrected mean: N = 42, declination = 056", inclination = -30", k = 22.6, crg5 = 4.7"). Geological implications of these new data are as follows.
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