1.10. The Northwest Peninsula, western Iceland, and the strandflat
COMMENT ON FIGURE 1.10.– Subsident morphology with a very large strandflat (<50 m, clear) south of the Northwest Peninsula and west of Iceland with fossilized coastal cliffs, flooded glacial valleys up to the upstream cirque (red arrow) and eroded platform in the Vestfirðir sector. Neogene and Quaternary glacial overdeepenings are indicated by black arrows.
In fact, this surface could have been shaped in approximately the Lower Oligocene and especially at the end of this epoch (Chattian). The first evidence of the glaciations of the northern hemisphere dates back to 9 My (beginning of the Tortonian) thus trace since this period a thermal subsidence and a tilting of the platform of at least 150 m west of Iceland, allowing an accentuation of the thermohaline circulation (section 3.1 of Volume 2). The flooded glacial valleys of the southern part of the Northwest Peninsula (Figure 1.10) also illustrate this evolution.
The eastern coast of the island, on the other hand, has a different history. It includes an older surface, located today at a depth of 1,000 m, which may have been shaped in the Bartonian age, a key period for the tectonics of the Atlantic margins (Chapter 3).
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