Figure 6 - uploaded by Juan Carlos Carracedo
Content may be subject to copyright.
Figure illustrating the origin of the Canaries in relation to a hotspot. HS: initial activity of the CHS, close to the continental-oceanic boundary. A: initial progression of volcanism along the continental-oceanic boundary (COB). B: general progression of volcanism induced by the displacement of the African plate. Ages in italics: the oldest dated subaerial volcanism of each island. The two scenarios (1 and 2) are explained in the text.
Source publication
The ideas presented in this paper have been greatly clarified and developed through our discussions with Uri ten Brink, Tony Watts, Tim Minshull, Robin Holcomb, Bruce Nelson and Hubert Staudigel. Stimulating comments from Hans Schmincke also helped us to focus our arguments. We thank all of them for their assistance in various stages of the prepara...
Contexts in source publication
Context 1
... volcanic rocks being emplaced within and above sediments (to produce the velocity inversion) and being fed from deep crustal intrusions (to produce the anomalous deep layer). They proposed that the devel- opment of this igneous province was due to passage of a hotspot that rejuvenated the ancient crust off Morocco from approximately 60 Ma (1 in Fig. 6) onwards. They trace the underplated igneous body to the north of the Canary Islands following a broad bathymetric arch across the continental rise west of the Fuerteventura-Lanzarote ridge that connects with the western part of the Canarian Archipelago. The arrival of the hotspot at this end of the island chain would have taken place, ...
Context 2
... a different model of the same general 'hot spot' type, Watts (1994) postulated a narrow asthenospheric feature encircling the Canaries and probably extending below the African continent (2 in Fig. ...
Context 3
... our model, we postulate that the Canaries origi- nated by an asthenospheric plume (Canas et al. 1994). The first volcanic manifestations of this hotspot would have been localized at the continental-oceanic bound- ary west of Fuerteventura (see Fig. 6). Sediment thick- ness at continental margins exceeding 10 km should be a major factor in modifying the strength of the lithos- phere. Lower overburden and conductivity of the sedi- ments are associated with significant weakening of the lithosphere (Vink, Morgan & Zhao, 1984). The gravity anomaly study of Watts & Marr (1995) provides ...
Context 4
... about 36 Ma (Abdel- Monem, Watkins & Gast, 1972) and39 Ma (Coello et al. 1992) and of Eocene-Oligocene age according to palaeontological evidence (Robertson & Stillman, 1979) -volcanism may have been spreading to the northeast and southwest along the weak continen- tal-ocean crust transition zone, producing the Fuerteventura-Lanzarote ridge (A in Fig. 6). As described by Dillon & Sougy (1974), interaction between the Canary Islands volcanism and the African continental margin is apparent off Cape Juby, where strongly magnetic volcanic seamounts extend in the lower continental slope along lines continuous with the Canary ...
Context 5
... from Lanzarote to Fuerteventura and oceanwards is inconsistent with the presently accepted geochronological and geological informa- tion, and reflects an unfounded link between the Canaries and the Atlas tectonism. After this initial stage, slow motion of the hotspot may have initiated the general westward trend followed by the Canaries (B in Fig. 6). The succession of the islands is broadly congruent with the westward progression of the hotspot; for reasons discussed above a perfect age-dis- tance correlation is not to be expected because of the very low velocity of the African plate relative to the plume reference frame. ...
Citations
... These volcanic islands record a general westward age progression with La Palma and El Hierro subaerial volcanism being the youngest at ∼1.7 and 1.1 Ma, respectively (Carracedo et al., 2001). Multiple models of formation have been argued as an explanation for the existence of the Canary Islands, including a mantle plume, edge-driven convection, or a tectonically controlled fracture (Anguita & Hernán, 2000;Carracedo et al., 1998;Duggen et al., 2009;Geldmacher et al., 2005;King & Ritsema, 2000;Zaczek et al., 2015). In recent years, a combination of a mantle plume edge-driven convection toward the "cold" African craton explains the apparent weak age progression of the Canary Islands as well as historic volcanism on both sides of the archipelago (Manjón-Cabeza Córdoba & Ballmer, 2022;Negredo et al., 2022;Troll & Carracedo, 2016). ...
The 2021 La Palma eruption (Tajogaite) was unprecedented in magnitude, duration, and degree of monitoring compared to historical volcanism on La Palma. Here, we provide data on melt inclusions in samples from the beginning and end of the eruption to compare the utility of both melt and fluid inclusions as recorders of magma storage. We also investigated compositional heterogeneities within the magmatic plumbing system. We found two populations of olivine crystals: a low Mg# (78–82) population present at the beginning and end of eruption, recording the maximum volatile contents (2.5 wt % H2O, 1,800 ppm F, 700 ppm Cl, 3,800 ppm S) and a higher Mg# (83–86) population sampled toward the end of the eruption, with lower volatile contents. Despite their host composition, melt inclusions share the same maximum range of CO2 concentrations (1.2–1.4 wt %), indicating olivine growth and inclusion capture at similar depths. Overall, both melt and fluid inclusions record similar pressures (450–850 MPa, ∼15–30 km), and when hosted in the same olivine crystal pressures are indistinguishable within error. At these mantle pressures, CO2 is expected to be an exsolved phase explaining the similar range of CO2 between the two samples, but other volatile species (F, Cl, S) behave incompatibly, and thus, the increase between the two olivine populations can be explained by fractional crystallization prior to eruption. Finally, based on our new data, we provide estimates on the total volatile emission of the eruption.
... The Canary Islands constitute an example of intraplate volcanism starting from the Oligocene (Carracedo et al., 1998). The archipelago consists of a group of seven main islands aligned along a roughly E-W direction, with their age being progressively younger toward the west. ...
Plain Language Summary
Oceanic volcanic islands have a complex internal structure. Our study is important to understand volcanic activity in its geodynamic context better. The last eruption occurred in the Cumbre Vieja volcanic complex on La Palma Island (2021) and had an unexpected magnitude in terms of lava volume, explosivity, and a significant impact on the economy and society of the island. This study used receiver function analysis to image the lithosphere up to a depth of 50 km. This seismological technique exploits the recordings of teleseismic events (i.e., earthquakes located between 30 and 90° from the stations) for this purpose. We used an advanced inversion technique to study the structure of the crust and the upper mantle beneath the volcano. The most relevant finding is a zone of anomalous low seismic velocities extending from 13 to 37 km depth. This zone is likely to host partial melt and magma chambers and extends over a much wider and thicker volume than expected from previous studies. Previous studies also identified two magma chambers: the upper one, located at about 10–15 km, and the lower one, beneath 25 km depth. These findings provide new insights into the current paradigms about the internal active oceanic volcanic islands.
... Oromí et al. 2015;Santos et al. 2015;Beierkuhnlein et al. 2021). El Hierro is a relatively young volcanic island, emerging about 1.1 Mya (Carracedo et al. 1998). Thus, it is possible that this lineage started diverging outside the island, colonising it at some point in the last million years. ...
The family Lophoproctidae Silvestri, 1897 includes small, blind millipedes adapted to endogeous environments. The genus Lophoproctus has five species with a mostly Mediterranean distribution, with only one species extending eastwards to Central Asia. Lophoproctus lucidus extends from southern France to north-western Africa and was recently reported for the first time from the Iberian Peninsula and the Canary Islands. However, some populations showed a certain degree of morphological differentiation, suggesting the existence of more than one species. To test this hypothesis, we study Iberian and Canarian populations using scanning electron microscopy and analyse mitochondrial and nuclear sequences of several Lophoproctus species, generating the first phylogenetic hypothesis for the genus. Our results confirm the existence of an unnamed species that is here formally described and named as Lophoproctus viator sp. n. The new species can be differentiated morphologically from the other species of the genus and represents an independent evolutionary lineage. We include a key to the morphological identification of Lophoproctus species.
... The relative importance of oceanic islands in world heritage is linked to the development of unique natural ecosystems (e.g., Galapagos) and human cultures (e.g., Easter Island), because of their extreme geographical isolation. They have remained isolated from continental landmasses since their formation, as they originate from volcanic activity at distant regions of the Earth's oceanic crust (Carracedo et al. 1998;McDougall 1971). ...
Oceanic islands constitute 0.05% of emerged land masses but account for 2% of UNESCO World Heritage Sites. Physical constraints have determined that the history of these remote territories is marked by globally unique forms of colonization and human cultures. A significant part of this heritage, located in coastal areas, is threatened by the mean sea level rise (SLR) due to anthropogenic climate change. This paper presents a regional approach to the risk estimation of SLR in the cultural heritage of oceanic islands, taking the Canary Islands (Spain) as an example. The Canary Islands is one of the most prominent oceanic archipelagos in the world (1500 km of coastline), where cultural heritage, preferentially located in the coastal areas (up to 50% in the first 1 km), nicely represents the two major stages of human occupation of islands (aboriginal and European). Through process-based modeling, high resolution flood maps were obtained for 20 climate scenarios and complete coverage of the archipelago. These maps were combined with detailed plani-metries of 343 officially designated cultural heritage sites, applying damage functions to relate flood depth with the type of construction and the historical period. The results indicate potential damage to 55 cultural heritage sites of the Canary Islands which could be significant in 15 of them. For these cases, it is recommended to study specific adaptation measures aimed at mitigating the flood risk, such as moving the heritage assets away from the hazard areas or reinforcing and protecting the structures to reduce their vulnerability.
... This is partly due to the relatively densely inhabited environment (and, hence, the considerable volcanic risk), and also the scientific controversies and debate within the Earth science community regarding the origin of volcanic activity in the archipelago, and the characteristics of the feeding mantle source Anguita and Hernán, 2000;Troll and Carracedo, 2016). One of the biggest open questions regarding the origin of volcanism in the Canary Islands is how the local mantle source has evolved after the breakup of Pangea (Hoernle et al., 1995;Carracedo et al., 1998;Anguita and Hernán, 2000;Gurenko et al., 2009;Troll and Carracedo, 2016). It has been suggested that the mantle underneath the Canary Islands is compositionally heterogeneous due to the coexistence of different mantle components. ...
The 2021 Tajogaite eruption at La Palma has represented a unique opportunity to investigate the characteristics of the mantle source feeding modern volcanism in the Canary Islands. With the aim of track the fingerprint of carbon in the local oceanic lithosphere-asthenosphere system, we report the isotopic composition of CO 2 (δ ¹³ C values versus Vienna Pee Dee Belemnite) in olivine- and clinopyroxene-hosted fluid inclusions (FI) from the 2021 Tajogaite lavas and from lavas/ultramafic xenoliths (olivine-clinopyroxenites, clinopyroxenites, dunites and harzburgites) from the nearby 1677 San Antonio eruption cone/lavas, in an attempt to characterize the origin and evolution of carbon within the local mantle source. Our results indicate that the 2021 and 1677 lavas exhibit δ ¹³ C values ranging from −4.94‰ to −2.71‰ and CO 2 / ³ He ratios from 3.37 to 6.14 × 10 ⁹ . Ultramafic xenoliths fall in a comparable range of values despite showing higher CO 2 concentrations. Our δ ¹³ C values fall within the range of carbon isotope results previously reported for the Dos Aguas cold spring located in the Taburiente Caldera (northern La Palma), suggesting an apparent carbon isotope homogeneity at the scale of the entire island. The (relatively narrow) δ ¹³ C vs. CO 2 / ³ He ratio range of La Palma samples is interpreted to reflect either i) variable extents of open-system degassing of a common mantle endmember having δ ¹³ C of ∼1.7‰, or ii) mixing between depleted mantle-like carbon (−6‰ < δ ¹³ C < −4‰) and crustal carbon (δ ¹³ C = 0‰) endmembers. Both models testify a crustal carbon component recycled in the local mantle. This component, also detected in mantle xenoliths from the neighboring island of El Hierro and the easternmost Lanzarote, indicates a regional characteristic of the mantle beneath the Canary Islands, interpreted as a result of infiltration of carbon-rich melts during past metasomatic events in the local mantle.
... Volcanism resulted in the formation of Garafía and Taburiente and then moved southward to form Cumbre Vieja volcano, at the southern part of the island. This southern system represents the last stage in the geological evolution of La Palma island, as volcanic activity has taken place exclusively on that part of the island for the last 123 ka (Carracedo et al., 1998). The most recent volcanic eruption of Cumbre Vieja is Tajogaite (2021) (Carracedo et al., 2001;Ward and Day, 2001), preceded by that of 50 Teneguía in 1971 (Fernández et al., 2021) and San Juan in 1940 (Fernández et al., 2021;Albert et al., 2016). ...
We report in-plume carbon dioxide (CO2) concentrations and isotope ratios during an active eruption of the Tajogaite Volcano. CO2 measurements inform our understanding of volcanic contributions to the global climate carbon cycle, and the role of CO2 in eruptions. Traditional ground-based methods of CO2 collection are difficult and dangerous, as a result only 5 % of volcanoes have been surveyed. We demonstrate that Unpiloted Aerial System (UAS) surveys allow for fast and relatively safe measurements. Using CO2 concentration profiles we estimate total flux to be 1.19 × 106 to 2.80 × 107 t day−1. Isotope ratios indicated a deep magmatic source, consistent with the intensity of the eruption. Our work demonstrates the feasibility of UASs for CO2 surveys during active volcanic eruptions, particularly in calculating plume characteristics.
... While volcanic activity in the Canary Islands has been intensively studied (e.g. Carracedo et al., 1998), less research has been done on the volcanic impacts to ecosystems and vegetation (Irl et al., 2019). ...
Volcanic eruptions have a strong environmental impact on surrounding forests. Trees are affected by mechanical damage, tephra deposition and volcanic gases. Oceanic islands are shaped by relatively frequent volcanic eruptions and thus offer the opportunity to study the effect of volcanic activity on biodiversity. We investigate the impact of volcanic gas emissions and tephra deposition during the 2021 Tajogaite eruption on the Canary Pine forests of the island of La Palma, Spain, characterized by monospecific stands of the endemic pine species Pinus canariensis C. Sm. ex D.C. Large quantities of volcanic sulphur dioxide caused chlorotic damage up to approximately 7 km around the crater, followed by widespread resprouting of P. canariensis.
To detect the spatial pattern of impacts, we sampled P. canariensis needles from all over the island of La Palma and analyzed their sulphur (S), nitrogen (N) and carbon (C) content. We found a strong increase of S needle content close to the crater, while C decreased significantly. S levels were strongly related to distance to the crater, C and N were mostly influenced by S content. Trees affected by volcanic gases allocate resources to resprouting, leading to lower levels of C due to translocation of C as a building block. Surprisingly, we found higher N levels in needles with high levels of S and a less clear pattern compared to C, likely due to a multitude of environmental factors influencing N needle levels.
We investigated how canopy damage patterns detected in Sentinel-2 remote sensing imagery after the eruption correlated to the in-situ needle contents. However, we did not find a clear correlation between in-situ needle values and spectral responses in remote sensing. While satellite images were well suited to analyse large scale patterns of canopy damage following the eruption, needle levels varied strongly on a local, tree-based level, which is not reflected in remote sensing imagery.
... Due to its geodynamics, the characteristics of the mantle source feeding the volcanism in the Canary Islands, although having been intensively studied for decades, remains a matter of debate in the geoscience community (Troll and Carracedo, 2016;Longpré and Felpeto, 2021;Civiero et al., 2023). This volcanism have brought to the surface an enormous spectrum of volcanic rocks that testify the complexity of the local mantle source: from carbonatites, nephelinites, basanites, tephrites, tholeiitic and alkali olivine basalts associated with shieldvolcanism processes to rhyodacites, rhyolites, trachytes and phonolites related to a highly explosive felsic volcanism (Schmincke, 1982;Abratis et al., 2002;Carracedo et al., 1998;Troll and Carracedo, 2016). Recent volcanism (since 1500 CE and including the 2021 Tajogaite eruption at La Palma) has been mainly characterized by effusive-like eruptions as registered in some islands such as La Palma, El Hierro, Tenerife and Lanzarote (Longpré and Felpeto, 2021). ...
... Between 1 and 3 g of rock powder were digested in ~15 ml of a 1:5 mixture of concentrated HNO 3 and HF. The samples were set on a hotplate for up to one week at ~160 • C, and subsequently (Anguita and Hernán, 2000;Day et al., 2010;Day and Hilton, 2021;Carracedo et al., 1998). The black dotted line indicates the likely path of the Canary hotspot (Holik et al., 1991). ...
... A feature common to the three slow-moving archipelagoes is that their constituent islands all have volcanism persisting until geologically recently, and in some cases to the present (Mascarenes: Duncan and Hargraves (1990) Carracedo et al. (1998). Whilst some islands have hiatuses within their volcanic sequences, a few spanning 3-5 million years, magmatism has always resumed. ...
Mantle-plume hotspot islands are a common focus of biogeographical studies, and models for the growth of their biodiversity often incorporate aspects of their physical evolution. The ontogenetic pathways of such islands have generally been perceived as simple, comprising successive episodes of emergence, growth, peak size, reduction and elimination. In this paper, we improve knowledge of island development by examining key physical data from 60 islands at eight archipelagoes in equatorial to mid-latitude regions of the Atlantic, Indian and Pacific oceans. Such landmasses achieve their maximum sizes within 200-500 kyrs. However, island longevity varies by up to a factor of 5 and is strongly controlled by the speed of the associated tectonic plate as it moves over the narrow, thermally-elevated conduit where volcanism is focused. At moderate to high speeds (40-90 mm/year; e.g., Gal apagos, Hawaii), lifetimes are no more than 4-6 Myrs. In contrast, the oldest landmasses (in the Cabo Verde, Canary, and Mascarene archipelagoes) are built upon slow-travelling plates (<20 mm/year) and date from the Miocene. Notably, Fuerteventura in the Canary Islands, where the rate is c. 2.5 mm/year, has existed since 23 Ma. Two processes likely sustain the sub-aerial elevation of these massifs: heat from the plume expands the underlying lithosphere thus increasing its buoyancy, which in turn inhibits cooling-contraction subsidence; protracted magmatic activity counteracts denudation. Furthermore, the Cabo Verde and the Canary archipelagoes sit within dry climatic regions, which likely reduced erosion and mass-wasting. Consequently, two ontogenetic models are presented, one for the edifices on the intermediate-and fast-moving plates, and a second for the constructions on the slow-moving plates. The development path for the former is similar to the schema that is commonly envisaged (see above) and takes place over c. 5 Myrs, whereas the one for the latter is rather different and involves quasi-continuous surface renewal plus the maintenance of elevation that lasts for c. 10-25 Myrs. The new information should permit a fuller understanding of how a hotspot island's physical development shapes its biota and inform the formulation of related theoretical models.
... The formation and geological evolution of the Canary Islands is still under debate and has given rise to different hypotheses; the propagating fracture, the uplift of tectonic blocks, the local Canary Islands rift, the blob model, etc. (Anguita & Hernán 2000). The most widely accepted hypothesis for its genesis is that its magmatism is associated with a hot spot related to the upwelling of an upper mantle plume (Holik et al. 1991;Carracedo et al. 1998;Negredo et al. 2022). As far as the island of Gran Canaria is concerned, and apart from the submarine construction phase (> 14.5 Ma) for which there is hardly any information, different magmatic phases of sub-aerial formation can be distinguished, which have been the subject of study in numerous investigations since the 1970s (Schmincke 1967, Feraud et al. 1981, Perez-Torrado et al. 1995, Carracedo et al. 2002, Van Den Bogaard 2013. ...
This research is a contribution to the mineralogical and physical–mechanical characterisation of the ignimbrites from Arucas (Gran Canaria Island), used as building stones under the commercial names of "Piedra de Arucas Lomo Tomás de León" and "Piedra de Arucas Rosa Silva". This stone has been used for more than five hundred years and is part of the local architectural heritage, but has also been exported to other regions of the world. To perform this characterisation, a chemical analysis was carried out using X-ray fluorescence (XRF), mineralogical and petrographic properties were obtained using polarised optical microscopy (POM), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Several physical properties were determined, namely: apparent density (AP), open porosity (OP), water absorption at atmospheric pressure (WA), water absorption by capillarity (WAC), ultrasound velocity (PWV) and colour. Mechanical properties were obtained through compressive strength (UCS), bending strength (BS), point load (PLT), indirect tensile (BTS) and energy at break (IR) tests. To evaluate the durability, the samples were subjected to salt crystallisation cycles (CS), SO2 action (AS) and salt spray (SS) and the abrasion resistance (AR) was determined. The results obtained show that, although both samples share the same lithology and belong to the same geological formation (Salic Formation, trachytic-phonolitic), they show very different properties. Porosity stands out as the property with the higher difference among the two studied varieties. Therefore, the application of these ignimbrites should be done accordingly, avoiding environmental conditions that promotes the wettability and/or the salt crystallisation.
