Leó Kristjánsson

Paleomagnetic observations on Late Quaternary basalts around Reykjavik and in the Reykjanes peninsula, SW-Iceland. Jökull 52, 21-32, 2003.

This paper reports paleomagnetic remanence directions from Late Quaternary lava units in the Reykjavík area and in the Reykjanes peninsula. In Reykjavík, samples were collected at about 30 sites in the interglacial "gray basalts" in the hope of finding unusual directions which might help in stratigraphic mapping in this region as well as documenting the behaviour of the geomagnetic field. The directions in these lavas are tightly grouped which indicates that the lavas were emplaced in a short time interval (< 50 kyr ?). One instance was found of a geomagnetic excursion, which probably occurred early in this volcanic phase. In Reykjanes, emphasis was on sampling lavas which might exhibit directions similar to the "Skálamælifell geomagnetic excursion". Lava sequences erupted during this excursion, of about 43 kyr age, were previously found to cover a few isolated areas in the region northeast of Grindavík. Their presence has already been of value in studies of local geomorphologic activity. The current work has since 1990 resulted in minor modifications in a map of the main areas covered by the excursion sequences, and one new area was found. Several lava flows erupted during an excursion of the geomagnetic field (possibly the Skálamælifell one) were sampled in mt. Fagradalsfjall.