23 research outputs found
The lava delta of Igueste de San Andrés (Anaga, Tenerife, Canary Islands)
Los restos de un delta de lava afloran dentro de la Serie I Media del Macizo de Anaga, en la parte nororiental de la isla de Tenerife (Islas Canarias), en el tramo bajo del Barranco de Igueste de San Andrés, a unos 90 metros de altura. El delta está formado principalmente por flujos de lavas basálticas de baja viscosidad que cubren lavas almohadilladas, brechas de fragmentos de almohadillas, más o menos resedimentadas, e hialoclastitas, ordenadas en foresets con buzamientos altos hacia el sur. Cubren erosivamente el delta aglomerados constituidos por fragmentos procedentes de las diferentes facies del delta y niveles de lavas y piroclásticos subaéreos, formados por pequeñas erupciones estrombolianas costerasThe remains of a lava delta occur within the volcanic succession called Serie I Media in the Anaga Massif, in the northeastern part of Tenerife Island (Canary Islands). The outcrop is located in the lower part of the ravine of Igueste de San Andrés, at about 90 meters high. The delta is formed mainly of flows of low viscosity basaltic lavas that cover pillowlavas, roughly resedimented pillow-fragment breccias, and hyaloclastites, in foreset bodies with high dips towards the S. The delta is covered by agglomerates constituted by fragments from the different facies of the delta and levels of lavas and subaerial pyroclasts, formed of small coastal strombolian eruption
Inventory of Geological Sites of Interest in the Canary Islands
En el marco de proyecto de investigación LIGCANARIAS (2018-2021) se ha realizado el Inventario de Lugares de Interés Geológico de las Islas Canarias, que forma parte del Inventario Español de Lugares de Interés Geológico (IELIG) para el dominio de este archipiélago. El inventario ha empleado la metodología del IELIG adaptada a un dominio geológico eminentemente volcánico, partiendo de los contextos geológicos regionales. Consta de 300 LIG: 53 en Gran Canaria, 47 en Tenerife, 54 en Lanzarote y Archipiélago Chinijo, 40 en Fuerteventura, 29 en La Palma, 23 en La Gomera y 21 en El Hierro. La principal novedad con respecto a los inventarios en otros dominios geológicos es la identificación de 33 LIG submarinos.Within the framework of the LIGCANARIAS research project (2018-2021), the Inventory of Geological Sites of Interest of the Canary Islands has been carried out, which is part of the Spanish Inventory of Places of Geological Interest (IELIG) for the domain of this archipelago. The inventory has used the IELIG methodology adapted to an eminently volcanic geological domain, based on regional geological frameworks. It consists of 300 geosites: 53 in Gran Canaria, 47 in Tenerife, 54 in Lanzarote and Chinijo Archipelago, 40 in Fuerteventura, 29 in La Palma, 23 in La Gomera and 21 in El Hierro. The main novelty with respect to the inventories in other geological domains is the identification of 33
submarine geosites.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEAgencia Canaria de Investigación, Innovación y Sociedad de la Informaciónpu
El Arco del Andén Verde, a big gravitational landslide in the northwestern coast of Gran Canaria (Canary Islands)
A sector of the northwestern coast of Gran Canaria (Canary Island) shows morphological and tectónica! characters, here described, wich demostrate the presence of a big gravitational landslide of the debris avalanche type, produced by the flank collapse of a basaltic shield volcano of Mid-Miocene ag
Características y procesos postemplazamiento de la ignimbrita de la playa de San Juan (Tenerife)
The Playa de San Juan Ignimbrite is a peralkaline pyroclastic flow that shows important facies variations depending on its emplacement position.
The ignimbrite is strongly welded, where slopes exceed about 2CP dipping fiamme, lamination and others structures indicate secondaty flow simultaneous with compaction and coolin
Pre-Cañadas volcanic episode in Tenerife Island
Based on new radiometric data, a Pre-Cañadas volcanic building of 3.5-3.0 Ma has been defined. This new building is mainly compared of basaltic rock cropping out in several gorges to the S of Cañadas Building, inside of the >, >, and > and > valley
A revision of the Paleontological Heritage from El Hierro UNESCO Global Geopark
La isla de El Hierro tiene 46 yacimientos paleontológicos, la mayoría de los
cuales se encuentran en cavidades volcánicas (tubos y simas) desarrolladas en los
materiales emitidos durante la actividad volcánica cuaternaria. Otros yacimientos
paleontológicos se pueden encontrar en paleoformas litorales, materiales aluviales
y acumulaciones escatológicas. Los fósiles más importantes que se encuentran en
estos yacimientos son restos de especies de lagartos gigantes y aves, algunos
extintos. Siete de estos depósitos se proponen en este trabajo como lugares de
interés geológico del Geoparque Mundial de la UNESCO de El Hierro, con base
en diferentes criterios de valoración científicos, socio-culturales y socio-económicos.
Pero es necesario realizar una carta paleontológica insular en la que se establezcan los límites cartográficos de cada uno de ellos, así como las medidas a
implementar para su conservación y puesta en valorThe island of El Hierro has 46 paleontological sites, most of which are
in volcanic cavities (tubes and chasms) developed in materials emitted
during Holocene activity. Other paleontological sites can be found in coastal
paleoforms, alluvial materials and scatological accumulations. The most
important fossils found in these deposits are the remains of giant lizard
species and birds, some of them extinct. Seven of these deposits have been
proposed as places of geological interest in the UNESCO Global Geopark
of El Hierro, based on different scientific, socio-cultural and socio-economic
assessment criteria. But it is necessary to make an insular paleontological
chart in which the cartographic limits of each of them are established, as
well as the measures to be implemented for their conservation and
valorizatio
Explosive eruption, flank collapse and megatsunami at Tenerife ca. 170 ka
Co-auteur étrangerInternational audienceGiant mass failures of oceanic shield volcanoes that generate tsunamis potentially represent a high-magnitude but low-frequency hazard, and it is actually difficult to infer the mechanisms and dynamics controlling them. Here we document tsunami deposits at high elevation (up to 132 m) on the northwestern slopes of Tenerife, Canary Islands, as a new evidence of megatsunami generated by volcano flank failure. Analyses of the tsunami deposits demonstrate that two main tsunamis impacted the coasts of Tenerife 170 kyr ago. The first tsunami was generated during the submarine stage of a retrogressive failure of the northern flank of the island, whereas the second one followed the debris avalanche of the subaerial edifice and incorporated pumices from an ongoing ignimbrite-forming eruption. Coupling between a massive retrogressive flank failure and a large explosive eruption represents a new type of volcano-tectonic event on oceanic shield volcanoes and a new hazard scenario