Application of multi-dimensional discrimination diagrams and probability calculations to acid rocks from Portugal and Spain [Aplicação de diagramas discriminantes multi-dimensionais e cálculos de probabilidades para rochas ácidas de Port
Por:
Verma S.P.
Publicada:
1 ene 2012
Resumen:
Discrimination diagrams have been used to decipher tectonic setting of old terrains. New discriminant-function based multi-dimensional diagrams for acid magmas were recently proposed. I present eleven case studies of Ediacaran-Early Cambrian to Permian acid magmas from Portugal and Spain to highlight the application of these diagrams and probability calculations. Two case studies on Rebordelo-Agrochão and Telões (Portugal) show a continental arc to collision transitional tectonic setting during the Early Carboniferous to Permian. The third case study on Oledo and Gouveia (Portugal) also indicated a continental arc to collision setting during the Early Ordovician. For the next three case studies on Gouveia, Castelo Branco, and Guarda from Portugal, and one on Jalama from Spain, a collision setting was clearly inferred during the Late Carboniferous to Permian. A collision setting was also indicated for Ossa-Morena (Portugal) during the Ediacaran-Early Cambrian. Finally, the last three case studies showed an island arc setting for Albrenoa (Portugal) and island arc to collision transitional setting for Serra Branca (Portugal) during the Devonian to Early Carboniferous, and an arc to collision setting for Évora (Portugal) during the Early Carboniferous. Possible reasons for generally consistent as well as some probably inconsistent inferences were also briefly discussed. © 2012 LNEG - Laboratório Nacional de Geologia e Energia IP.
Filiaciones:
Verma S.P.:
Departamento de Sistemas Energéticos, Centro de Investigación en Energía, Universidad Nacional Autónoma de México, Privada Xochicalco s/no., Centro, Apartado Postal 34, Temixco, Mor., 62580, Mexico
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