The British Tertiary Igneous Province: Palaeomagnetism and Ages of Dykes, Lundy Island, Bristol Channel

Abstract

Summary Of 66 dykes collected 52 gave stable directions: 44 reversed, 4 normal and 4 intermediate. The mean direction of magnetization was N3 - 6 E, + 62 7 (down,) equivalent to a pole position of 82.6 ON, 155.0 E. This is significantly different from the present pole and displays right-handed farsidedness. The bulk, at least, of the dykes fall within the apparent span 45-54 My. Yet they display approximately the same small proportion of normal dykes as do the older dyke swarms of the province which were formed during a different polarity period or periods.