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Crater Basalt volcancinder cones 1359 m / 4,459 ft
Argentine/Chili (sud), South America, -42.02°S / -70.18°W Condition actuelle: (probablement) éteint (0 sur 5)
Style éruptif tipique: strombolian, effusive
Eruptions du volcan Crater Basalt: none in recent times Crater Basalt photos du volcan Derniers séismes proches:
The volcanic field covers an area of 700 sq km, and consists of cinder and spatter cones with many overlapping blocky basalt lava flows. Introduction:The Crater Basalt volcanic field lies about 400 km east of the Perú-Chile trench and is related to extension along the broad regional, NW-SE-trending Gastre fault system. The erupted lavas range in composition from alkali basaltic, basanitic, to trachybasaltic.Radiometric K/Ar ages of lava samples seem to indicate 3 periods of activity: the oldest lava flows were erupted around 1 million years ago (in the center and eastern part of the field, Cerro Ventana, Pinchuleu, Contreras) (1.04 ± 0.43 million years), the second group was active around 600,000 years ago in the central-northern parrt (Cerro Volcán, Fermin). The youngest group (Cerro Antitruz, Negro) was dated around 0.23 ± 0.10 million years ago and forms the western part of the field scoria cone on the Rio Chico-fluvial terrace. from E to W (old-young): Cerro Contreras (1004 m) is deeply eroded, only 2 volcanic dikes are well preserved. Cerro Pinchuleu (1005 m) erupted at least 4 lava flows. Cerro Ventana (1008 m) is a partially eroded cinder cone. 7 lava flows were fed from this vent. Cerro Loma Huacha (959 m) is a cinder cone with a small parasitic cone on its northeast flank. Its crater is 50 m wide and breached to the north. Cerro Fermín (1153 m) is one of the largest cinder cones in the Crater Basalt field large cand produced 6 lava flows. It is composed of spatter, cinder and bombs. Cerro Volcán (1025 m) is a scoria conewith a 100 m wide and 30 m deep crater. Cerro Negro (1159 m) is the highest cone of the Crater Basalt volcanic field. It produced at least 4 block lava flows with well-developed channels, which traveled to the west, east, and then NE, where they joined the flows of the Gastre trench near Provincial road 4. Cerro Antitruz (1100 m) is a pyroclastic cone in the western part of the volcanic field, and is probably the youngest of the group. --- Sources: - PÉCSKAY et al (2007) "PRELIMINARY K/Ar GEOCHRONOLOGY OF THE CRATER BASALT VOLCANIC FIELD (CBVF), NORTHERN PATAGONIA", Revista de la Asociación Geológica Argentina 62 (1): pp 25-29 - Mena et al (2005) "Paleomagnetism of postglacial beek-arc basalts in Gastre (northwestern Patagonia)", 6th International Symposium on Andean Geodynamics (ISAG 2005, Barcelona) , Extended Abstracts: 504-507 Crater Basalt Photos:
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