Palaeomagnetism of tertiary volcanic rocks from the Ethiopian southern plateau and the Danakil block
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Vols. 1-18 (1924-1944), ISSN 0044-2801
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Abstract
Remanent magnetization of 92 samples (22 sites) collected from Oligocene basalts from the Ethiopian southern plateau (location 9.1°N, 41°E) yields a palaeomagnetic pole at 75.1°N, 170.3°E with A95 = 6.4° after AF-cleaning. This pole agrees with the Eocene-Oligocene pole for the western plateau. Palaeomagnetic data of 125 samples (26 sites) from Early Pliocene basaltic rocks from the Danakil block (12.7°N, 42.5°E) yield a pole at 79.5°N, 258.8°E with A95 = 2.6°. The deviation of this pole position from other Miocene Pliocene poles for Africa is consistent with the hypothesis of 10° counter-clockwise rotation of the Danakil block since the Early Pliocene. On theoretical grounds however this amount of deviation may also be caused by not having completely averaged out secular variation due to insufficient sampling.
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References
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