Morphology of the Reykjanes ridge junction with the rift zones of Iceland

Abstract

The joint zone between subaquatic Reykjanes Ridge and Icelandic rift zones known as Reykjanes Rift Zone is a unique transform zone formed in conditions of interaction between the mantle plume and the mid-oceanic ridge. Its morphostructures include a row of en-echelon volcanic systems with oblique extension. The modern tectonic and volcanic relief was formed almost completely during Holocene: the previous landforms were reworked or destroyed by erosion of the Late Pleistocene glaciation. Morphology of the Reykjanes Rift Zone is transitional between the Reykjanes Ridge and the adjacent Western Rift Zone from the northeast. Unlike the Reykjanes Ridge, volcanic activity is not concentrated with in axial volcanic ridges, but is confined by eruptive centers represented by fissure volcanoes. Central volcanoes, in contrast to the Western Rift Zone, are not expressed in topography. Oppositely, tectonic activity increases with distance from the Reykjanes Ridge. Fault scarps reach their largest size within the Western Rift Zone, where Thingvellir graben is located. At the same time, the tectonic and volcanic landforms of the Reykjanes rift zone are in paragenetic association, appearing sequentially during the episodes of riftogenesis.

Keywords

• iceland
• rift zones
• reykjanes peninsula
• tectono-magmatic activity
• volcanism