Villarrica Volcano, Chile
Villarrica volcano is located in the volcanic chain of the Southern Volcanic Zone (SVZ) of the Chilean Andes. It is one of the most active Chilean volcanoes with 59 documented eruptions since 1558 (Petit-Breuilh and Lobato, 1994; Lara and Clavero, 2004). It has an active summit lava lake (30 to 60 m diameter) since the last eruption in 1984-85 (Calder et al., 2004). The Villarrica volcano (2,850 m Above Sea Level) forms a NW-SE volcanic chain, together with the Pleistocene-Holocene Quetrupillán and Lanín stratovolcanoes, that is oblique to the recent volcanic arc and to a main structure located in the region, the Liquine-Ofqui Fault Zone (LOFZ; Hickey et al., 1989; Cembrano, 1990; Cembrano et al., 1992; Cembrano and Moreno, 1994; López-Escobar et al., 1995). This structure probably corresponds to an old fracture in the crust, which has been used by Quaternary magmas to reach the surface (Franzese, 1995). Eruptive activity of the Villarrica volcano has commonly been considered to be dominantly effusive to slightly explosive (mainly strombolian eruptions, González, 1972; Fuentealba et al., 1985; Moreno,1993). However, recent detailed volcanologic and stratigraphic studies (Moreno, 1993; Clavero and Moreno, 1994,1998; Moreno et al., 1994; Clavero, 1996) show intense explosive postglacial activity with, at least, 15 mapeable deposits of pyroclastic flows and surges in the last 14 ka, two of which were of large volume: the Licán and Pucón ignimbrites. The basement of the Villarrica volcano consists of intrusive and volcanic rocks that range in age from Late Paleozoic to Miocene (Aguirre and Levi, 1964; Parada, 1975; Moreno and Parada, 1976; Munizaga et al., 1988), and sedimentary deposits related to the middle to late Pleistocene glaciations in the region (Moreno, 1993, Clapperton, 1993, Clayton et al., 1997). Intrusive rocks are predominantly granodioritic in composition and range in age from late Paleozoic to Upper Miocene (Munizaga et al., 1988). The volcanic rocks correspond mainly to hypabyssal andesitic bodies from the Upper Cenozoic that crop out on the western side of the volcano (Moreno, 1993), while the younger sedimentary deposits range in age from Pleistocene to Holocene and consist of glacial, lacustrine and fluvial deposits, moderately to completely unconsolidated. More information is available on Wikipedia
Today we feature Villarica Volcano, in Chile. On 3 March 2015, Villarrica Volcano erupted in the early hours of the morning, emitting gas, ash, and lava up to 1000 metres (3,300 feet) into the air. After the initial eruption, no further ash, lava, or toxic gases were emitted from the volcano. Thousands of residents of Pucon, the closest town to the volcano, were evacuated since initial signs of eruption began, and further eruptions of the volcano are expected in the oncoming weeks. The last major eruption of Villarrica Volcano was in 1985, though numerous small-scale eruptions have affected the region since then. The major danger associated with the volcano is not the ash or the lava, but the lahars, or volcanic mudflows that are caused by volcanic activity, reported to have killed over 100 people in the past century. Villarrica Volcano is considered one of Chile's most active volcanoes, approximately 750 kilometres (470 miles) south of Santiago. It is the furthest west volcano of a series of three large stratavolcanoes perpendicular to the Andean mountain chain along the Gastre Fault. The volcano serves as a popular spot for hiking and sightseeing, and the surrounding region has been made into a Chilean national park. Villarrica Volcano has primarily basaltic-andesitic magma, with a silica content and viscosity somewhere between mafic basalt and intermediate andesite. As a result, eruptions at the volcano's summit are often unpredictable, ranging from violent to mild. One interesting characteristic of Villarrica Volcano is the fact that it has a small, intermittent lava lake within its crater at the peak of the stratavolcano cone. This is a relatively rare occurrence among volcanoes, especially stratavolcanoes. Villarrica Volcano typically demonstrates strombolian eruptions, with significant ejection of pyroclastic material, lava flows, and massive lahars (mud and debris flows) caused by the combination of rainfall, snow, glacier ice, and the underlying magma and gasses of the volcano. These images acquired by the Landsat 8 satellite in February and March, aim to show the volcanic activity during the month of March. In fact in this comparison we can to see the lava flow along the slopes of Villarrica (large gray area near the crater). Another aim of these images is to promote the opportunity to download Landsat data through the ESA portals, where images captured every day are made available in near real time to the users and the scientific community. Landsat full resolution data products are freely available for immediate download at:  View Landsat 8 OLI high resolution image - Before eruption (JPG 483 KB) View Landsat 8 OLI high resolution image - After eruption (JPG 359 KB)
These images acquired by the Sentinel-1 satellite in February and March, show Villarrica Volcano using a merge of two radar images. Sentinel-1 is a space mission from ESA of the Copernicus Programme, consisting of a constellation of two satellites. The payload of Sentinel-1 is a Synthetic Aperture Radar in C-band that provides continuous imagery (day, night and all weather). This merged image also aims to demonstrate the future monitoring of Earth with Sentinel satellites. More information is available on Wikipedia  View Sentinel-1 high resolution merge (JPG 209 KB)
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