Melting of a subducting oceanic crust from U-Th disequilibria in austral Andean lavas
Article Abstract:
There is a uniform excess of Th, the radiogenic product of U, over U in young adakites from the Andean austral volcanic zone south of the triple junction where the Chile ridge subducts beneath South America. These adakites also show variable Th isotope ratios. It seems likely that the adakites were formed by around 20% equilibrium melting as a result of amphibole decomposition in a heterogeneous oceanic crust. Adakites may have been added to the continental crust throughout Earth's history when an ocean crust that was young and hot enough was subducted.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
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Post-rifting stress relaxation at the divergent plate boundary in Northeast Iceland
Article Abstract:
Geological strain resulting from stress between adjacent tectonic plates has been detected for the first time at the divergent or spreading plate boundary in Northeast Iceland. Global Positioning System (GPS) satellite data confirmed the predicted existence of such stress, which is thought to arise as the elastic lithosphere interacts with the anelastic asthenosphere after tectonism at the plate boundaries. A model of tectonic activity in which a thin elastic layer lies on top of a viscous layer probably accounts for the GPS and magnetotelluric data.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
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Geochemical evidence for the melting of subducting oceanic lithosphere at plate edges
Article Abstract:
Research is presented concerning the formation of adakites during the slab-melt process which occurs at the Aleutian islands and Kamchatka peninsula. The use of adakites as tracers in the study of plate tectonics is discussed.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2001
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