![]() ![]() While the more western islands (El Hierro and La Palma) are still in the juvenile stage, characterized by high eruption rates and fast volcanic growth of the islands, the eastern islands (Fuerteventura and Lanzarote) are in a terminal rejuvenated stage, with a predominance of erosive processes on the volcanic deposits ( Carracedo et al., 1998, 2002). Similarly to other intraplate volcanic islands, the Canarian archipelago also displays the typical hotspot volcanic stages of evolution: juvenile (shield) stage, volcanic quiescence stage and rejuvenated stage. This progressive decrease in age, from east to west, is due to the movement of the African plate over a mantle plume ( Carracedo et al., 1998, 2002 Holik, Rabinowitz, & Austin, 1991 Klügel, Hansteen, van den Bogaard, Strauss, & Hauff, 2011 Schmincke & Sumita, 2010 van den Bogaard, 2013). The archipelago and the seamounts, which form the Canary Volcanic Province, have an internal age-progression towards the SW, from the oldest age of circa 68 Ma for the Lars/Essaouria seamount to 1.12 Ma for the El Hierro island ( Figure 1(b,c)) ( Geldmacher, Hoernle, Bogaard, Duggen, & Werner, 2005 Geldmacher, Hoernle, van den Bogaard, Zankl, & Garbe-Schönberg, 2001 van den Bogaard, 2013 Zaczek et al., 2015). The spatial and chronological evolution of the Canary Islands chain also comprises a group of seamounts located northeast of the archipelago ( Figure 1(b)), with Lars/Essaouria, Anyka/Rybin, Dacia, Selvagem and Conception Bank being the largest ones. ![]() These islands developed in a geodynamic setting characterized by a thick, rigid and old (Jurassic) oceanic lithosphere lying close to a passive continental margin and on a slow-moving (2 cm/yr) plate (the African plate) ( Silver, Russo, & Lithgow-Bertelloni, 1998). The Canaries, which comprise seven main islands and several islets, are situated between 29° 25′ and 27° 37′ N and 18° 10′ and 13° 20′ W, and the total emerged area is 7490 km 2. ![]() This region is located in the NE Atlantic Ocean between 14° and 40° N (subtropical environment), bordering the African coast ( Figure 1(a)). The Canary Islands are part of the group of archipelagos known as Macaronesia, in which Azores, Madeira and Cape Verde are also included. Our reconstruction considers two key evolutionary stages leading to the present day DTM (eruption affected by erosion), specifically pre-eruption (surface unaffected by eruptions) and immediate post-eruption (eruptive deposits unaffected by erosion) DTMs.Ĭomparison of these DTMs in a GIS framework gives 2D and 3D models that allow a proper understanding of the topographic changes that have taken place in the areas affected by Holocene volcanic eruptions in both the construction stages and their subsequent degradation. The aims of this work are 1) to present a detailed cartography of the common units in monogenetic volcanic fields (cones, tephra air-fall deposits, and lava flows), together with geomorphologic and stratigraphic observations of these units, and with the surrounding substrate, and 2) to develop a methodology for generating palaeogeomorphological reconstructions of Digital Terrain Models (DTMs). Here, the temporal succession of monogenetic volcanisms was inferred by geochronology, using radiocarbon dating of charcoal beneath and included in the lava flows, and relative dating based on the stratigraphic and geomorphologic relationships of the volcanic deposits. A comprehensive chronology of Holocene eruptions is essential for both the interpretation of the geological evolution and the assessment of volcanic hazards of a volcanic area. ![]()
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