Evidencias de interaccion magma-agua durante el ciclo eruptivo explosivo de la Ignimbrita Lican (13.800 años AP), volcan Villarrica (sur de Chile).
Evidence of magma-water interaction during the 13,800 years BP explosive cycle of the Licán Ignimbrite, Villarrica volcano (southern Chile)
| dc.contributor | en-US | |
| dc.contributor | es-ES | |
| dc.creator | Lohmar, Silke | |
| dc.creator | Robin, Claude | |
| dc.creator | Gourgaud, Alain | |
| dc.creator | Clavero, Jorge | |
| dc.creator | Parada, Miguel angel | |
| dc.creator | Moreno, Hugo | |
| dc.creator | Ersoy, Orkun | |
| dc.creator | Lopez-Escobar, Leopoldo | |
| dc.creator | Naranjo, Jose Antonio | |
| dc.date | 2010-06-24 | |
| dc.identifier | http://www.andeangeology.cl/index.php/revista1/article/view/V34n2-a04 | |
| dc.identifier | 10.5027/andgeoV34n2-a04 | |
| dc.description | El Villarrica es un estratovolcan activo, situado en la Zona Volcanica de los Andes del Sur. Hace aproximadamente 13.800 años AP (edades 14C no calibradas), este volcan sufrio un evento explosivo importante que dio lugar a la emision de una secuencia de flujos piroclasticos, conocida como la 'Ignimbrita Lican', cuyo volumen ha sido estimado en -10 km3 (no-ERD, Equivalente de Roca Densa). Los depositos consisten, principalmente, en flujos piroclasticos macizos y oleadas piroclasticas estratificadas. Las facies tipicas que resultan de los flujos presentan bombas escoriaceas, bloques juveniles densos, fragmentos liticos y lapilli escoriaceo, inmersos en una matriz cuyo color varia entre gris oscuro y pardo. Por otro lado, los depositos de oleadas estan constituidos por escorias de tamaño lapilli, contenidas en una matriz fina, de color pardo claro o amarillo verdusco. La composicion de los clastos juveniles es andesitico-basaltica a andesitica (55 a 58% en peso de Si02). Este articulo presenta la estructura interna general de estos depositos, observaciones realizadas en el MEB (Microscopio Electronico de Barrido) y datos litologicos y granulometricos, con el proposito de determinar el papel que jugo la fragmentacion debido a la interaccion magma-agua durante la erupcion. Los resultados indican que la expansion de gases pudo ser un proceso importante. Sin embargo, caracteristicas de terreno, texturas superficiales de cenizas, el enriquecimiento en fragmentos liticos hacia el techo de las secuencias y la palagonitizacion variable del vidrio de la matriz sugieren un incremento de la intervencion del agua durante el transcurso de la erupcion. | es-ES |
| dc.description | Villarrica is an active stratovolcano located in the Southern Andean Volcanic Zone. About 13,800 years BP (conventional radiocarbon ages), this volcano experienced major explosive eruptions which resulted in the emission of a sequence of pyroclastic flows, known as the 'Licán Ignimbrite', the bulk volume of which is estimated in -10 km3 (non-DRE, Dense Rock Equivalent). The deposits mainly consist of massive pyroclastic flows and stratified pyroclastic surges. Typical flow fades showscoriaceous bombs, dense juvenile blocks, lithics and scoria lapilli immersed in a dark-grey to brownish matrix, whereas surges expose lapilli-sized scoria in a fine, light-brown or yellow-green matrix. Juvenile clasts range from 55 to 58 wt% Si02 in composition. This paper describes the general architecture of the Licán Ignimbrite deposits and, based on SEM (Scanning Electron Microscope) observations and lithologic data, emphasizes the role of fragmentation due to magma-water interaction during the eruption. The results indicate that gas expansion was an important process. However, field characteristics, surface textures of ashes, enrichment of lithics towards the top of the sequence and variable palagonitization of matrix glass show the intervention of water since the initial stages of the eruption and its increasing influence during the later phases. | en-US |
| dc.format | application/pdf | |
| dc.format | text/html | |
| dc.language | eng | |
| dc.publisher | Servicio Nacional de Geología y Minería | en-US |
| dc.relation | http://www.andeangeology.cl/index.php/revista1/article/view/V34n2-a04/492 | |
| dc.relation | http://www.andeangeology.cl/index.php/revista1/article/view/V34n2-a04/html | |
| dc.source | Andean Geology; Vol 34, No 2 (2007); 233-248 | es-ES |
| dc.source | Andean Geology; Vol 34, No 2 (2007); 233-248 | en-US |
| dc.source | 0718-7106 | |
| dc.source | 0718-7092 | |
| dc.title | Evidencias de interaccion magma-agua durante el ciclo eruptivo explosivo de la Ignimbrita Lican (13.800 años AP), volcan Villarrica (sur de Chile). | es-ES |
| dc.title | Evidence of magma-water interaction during the 13,800 years BP explosive cycle of the Licán Ignimbrite, Villarrica volcano (southern Chile) | en-US |
| dc.type | info:eu-repo/semantics/article | |
| dc.type | info:eu-repo/semantics/publishedVersion | |
| dc.type | es-ES | |
| dc.type | en-US |
This item appears in the following Collection(s)
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Andean Geology
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