The Holocene Murta basalts represent a small volume monogenetic centre located in the northern Patagonian Andes at the latitude of the Chile Triple Junction. These basalts show morphological evidence of subglacial eruption. They are locally porphyritic with large plagioclase feldspar, clinopyroxene and olivine megacrysts. The major- and trace-element concentrations, REE patterns, and isotopic data, distinguish them clearly from the other Holocene arc basalts or the Palaeocene back-arc lavas. Their asthenospheric signature is in accordance with a geodynamic context characterised, since the Miocene, by the subduction of the Chile Ridge below the South American Plate and the progressive development of a slab window.
|Translated title of the contribution||Petrology and geochemistry of the Murta basalts: A subglacial eruption in the Patagonian Andes (46°lat. S.), Chile. Relationship with the subduction of the Chile Ridge|
|Number of pages||7|
|Journal||Comptes Rendus de l'Academie de Sciences - Serie IIa: Sciences de la Terre et des Planetes|
|Publication status||Published - Dec 1998|
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Ocean Engineering