Greinar (Vísindafélag Íslendinga) - 01.01.1976, Blaðsíða 57

55
the Kolbeinsey Ridge and the northern volcanic zone in Iceland
were taken up by the Dalvik fault, the total horizontal motion in
post-glacial time would he less than 200 meters calculated from
the spreading rate. Since some of the transform motion is taken
up by the parallel Húsavík and Grímsey faults, the total motion
along the Dalvík fault is probably considerably less than 100 meters
in post-glacial time and could conceivably be masked by erosion.
DISCUSSION
VHien the results of this study are added to the results of Sae-
mundsson’s study (5), a rather complex tectonic picture emerges.
A series of N-S trending ridges and troughs are superimposed on
the pattem of parallel WNW trending strike-slip faults described
20°W I7°W
Fig. 4: A schematic diagram showing the spatial relationship between the proven
and inferred strike-slip faults, the ridge-and-trough structures and the northem
volcanic zone of Iceland as marked hy the swarms of normal faults an open fis-
sures. The westernmost trough is the Eyjafjördur trough, the easternmost one is
the Axarfjördur trough. The fault swanns are drawn according to Saemundsson
[1974].