The Quaternary calc-alkaline volcanism of the Patagonian Andes close to the Chile triple junction: geochemistry and petrogenesis of volcanic rocks from the Cay and Maca volcanoes (∼45°S, Chile)

Seismicity distribution in the vicinity of the Chile Triple Junction, Aysén Region, southern Chile

“…2). The morpho-structural setting is controlled by NEe SW and NWeSE structures related to the LOFS (D'Orazio et al, 2003). The coastal domain is mainly characterized by Palaeozoic and Triassic metamorphic rocks located on the archipelago islands.…”

“…S, encompassing the Main Cordillera of the Andes and the eastern portion of the Coastal Cordillera (Pankhurst et al, 1999), and including the highest altitudes in the area (up to 2000 m.a.s.l.). Quaternary volcanism is also present in the region with strato-volcanoes Hudson, Maca, Cay and several monogenetic cones, which occur over the volcanic arc (D'Orazio et al, 2003). The active Hudson volcano had its last major eruption on August 1991, producing more than 4 km 3 of pyroclastic material transported in NE direction (Naranjo and Stern, 1998).…”

Fallout and distribution of volcanic ash over Argentina following the May 2008 explosive eruption of Chaitén, Chile

“…The glass forms a single compositional group, but the 3 May data cover a discrete domain within this, suggesting slight compositional differences between eruption phases. (c -d) Rb and Zr against silica for regional volcanics containing >60 wt % SiO 2 [D'Orazio et al, 2003;Gutiérrez et al, 2005;Kilian and López-Escobar, 1991;López-Escobar et al, 1993;Naranjo and Stern, 2004;Notsu et al, 1987]. Points are shown for bulk tephra or lava from Hudson, occupying a distinct group [cf.…”

Boron and other trace element constraints on the slab-derived component in Quaternary volcanic rocks from the Southern Volcanic Zone of the Andes

“…Contamination of the slab derived component to the SSVZ mantle source has been discussed by D'Orazio et al (2003) based on geochemical data of Cay and Maca volcanoes. They suggested that addition of small amounts (<1%) of both bulk sediment and slab-derived fluid to the depleted mantle is attributable to the mantle source of the Cay and Maca volcanoes.…”