Some aspects of the late Tertiary geomagnetic field in Iceland

Abstract

Summary. In 1972–78, the late N. D. Watkins and others carried out ajoint field programme of geological mapping in the Mio‐Pliocene flood basalts of Iceland, including sampling for K‐Ar dating and palaeomagnetic research. The major part of the palaeomagnetic sampling is represented by 2462 lavas in five long composite sections through the lava pile. This paper deals with various statistical properties of this data set. It is concluded that geomagnetic reversals occur more frequently than is assumed in the current ocean‐floor polarity time‐scale. There is no evidence for significant asymmetries between normal and reverse polarity states of the field, neither as regards chron lengths, secular variation, or virtual dipole moment magnitude. Intensities of remanence in these lavas are shown to be well approximated in terms of a hyperbolic distribution. The latitude distribution of virtual magnetic poles can be fitted with a Bingham function having k′∼ 4.5, and low‐latitude poles do not occur preferentially in any particular longitude interval. Copyright © 1982, Wiley Blackwell. All rights reserved