Cenozoic Evolution of Iceland and the Cryosphere

Neogene and Pleistocene geodynamics: the paleoseismic evolution of Armorica (Western France)

“…This 400-ka seismic and/or tectonic event has been recognized as a major boundary in Quaternary stratigraphy along the North Atlantic coasts, as previously mentioned by Mangerud et al (1996). In Iceland, the event followed a period of dated high sub-glacial volcanic activity, suggesting some enhanced activity on the mid-Atlantic Ridge (Van Vliet-Lanoë and Guillou, 2021).…”

“…This seems valid for the entire North Atlantic coast (Mosar et al, 2002;Japsen et al, 2014). This PS7-1 surface has been partly abraded by platform glaciers, forming a strandflat, but had commonly already been deeply scoured by ice streams that surged from a ~9 Ma former fluvial system (Table 1) (Mosar et al, 2002;Van Vliet-Lanoë and Guillou, 2021). This indicates that the Late Miocene-Pleistocene platform reshaping in Brittany was not an exception along the passive margins of the Atlantic Ocean.…”

“…The platform shaping along the Atlantic margins, thus, accelerated during the Neogene and Pleistocene due to doming/ uplift events and occurred alongside the formation of glaciers during the onset of the glaciations (Japsen et al, 2014;Van Vliet-Lanoë and Guillou, 2021).…”

“…Quaternary (marine or fluvial) staircase terraces have commonly been attributed to tectonic activity (Lenôtre et al, 1999;Kirby and Whipple, 2001;Coutard et al, 2006;Antoine et al, 2007). In Western Europe, the Quaternary interglacial raised beaches, recorded on the lower platform south of the Dover Strait, are commonly limited in age to the last ~500 ka (MIS 15), as in Armorica (Van Vliet-Lanoë and Guillou, 2021). In Armorica, the absence of Quaternary interglacial raised beaches between 0.7 and 1.4 Ma suggests a lowered HS altitude than the current global SL average (±10 m or less) between late MIS 22 and 16-the oldest major Quaternary glaciations.…”