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Iceland Within the Northern Atlantic, Volume 1


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target="_blank" rel="nofollow" href="#ulink_8a053ad3-cc4e-5059-a478-0fb93d6bb6da">Figure I.22. A subglacial tabular volcano: the Herðubreið, north of Vatnajökull, North Volcanic Zone (Brigitte Van Vliet-Lanoë©)

Photo depicts Jokulsa a Kreppa north of Vatnajokull with hyaloclastite or tindar ridges. Photos depict (A) Bruarjokull outlet. (B) One of the Dettifoss waterfalls. (C) The Haslsón dam on the Jokulsa a Bru. (D) The Fannahlid aluminum plant.

      In this two-volume book, we will present the geological and glacial history of this island, its current tectonic and volcanic activity and the impact of its formation on the climatic evolution of the last few millions of years. Volume 1 replaces Iceland within the geological framework of the North Atlantic, and describes its tectonic and geodynamic evolution. Volume 2 (Van Vliet-Lanoë 2021) is dedicated to the study of the interactions between Icelandic volcanism and external geodynamics, i.e. with glaciations and the climatic evolution of the Atlantic zone during the Neogene and the Quaternary.

      For color versions of the figures in this Introduction see, www.iste.co.uk/vanvliet/iceland1.zip.

      1

      Iceland, in the Lineage of Two Oceans

       Brigitte VAN VLIET-LANOË and Françoise BERGERAT with the collaboration of René MAURY, Hervé GUILLOU and Laurent GEOFFROY

      The existence of Iceland probably dates back to the Oligocene. Its position east of Greenland and its insularization make it a key witness of the great changes controlling the evolution of the oceanic circulation. It has thus controlled the evolution of the climate since the Neogene, through the North Atlantic Current. It has also been, since 9 My, a key recorder of the onset of glaciation in the northern hemisphere, and also of glacier–volcanism interactions. Its location in the middle of the Greenland–Faroe Islands Ridge (GFIR) controls the descent of cold salty waters from the Arctic and North Atlantic into the thermohaline circulation section 3.4 of Volume 2).

Map depicts the Northeast Atlantic Ocean and the Labrador–Baffin axis.

      These submerged domains are made up of lithospheres of oceanic and continental nature (section 3.2) with, sometimes, uncertain limits between these two types.

      Figure 1.2. (a) Geological map of Iceland, originally at 1/600,000e (H. Johanesson 2014). Náttúrufræðistofnun Ísland (Icelandic Institute of Natural History) (available at: https://en.ni.is/resources/publications/maps/geological-maps)

Map depicts the current morphology of Iceland. (a) A volcanic island shaped and occupied by glaciers and whose submarine plateau was indented by Neogene glaciations (GEBCO 2019 data). (b) Ice-free topography.