Congratulations to team member J\u00fcrgen von Raumer for his latest paper on the Central Iberian basement-A multiphase evolution. <\/i><\/p>\n
The Cambro\u2010Ordovician rhyodacitic to dacitic volcanics from the Central Iberian basement, currently known as Ollo\u2010de\u2010Sapo (toads eye), have been reported as a specific group of felsic porphyritic rocks with blue quartz and large phenocrysts of K\u2010feldspar, in a partly vitreous or fine\u2010grained matrix. Interpreted to form Cambro\u2010Ordovician volcanic domes, they are accompanied by tuffs, ignimbrites and products of reworking in a near\u2010surface environment.<\/p>\nRead More<\/span> The coarse\u2010 to fine\u2010grained rocks exhibit rather large K\u2010feldspar phenocrysts, plagioclase and rounded blue quartz, representing former corroded phenocrysts. Their colouration indicates unmixing of TiO2 at around 900 \u00b0C during cooling from relatively high crystallisation temperatures, indicating their origin at hot lower crustal conditions. We propose at least a two\u2010step evolution (1) starting around 495 Ma in the lower crust of a collapsing cordillera, generating a phenocryst\u2010rich mush and adiabatic melting of the lower crustal protolith to produce the spectacular Ollo\u2010de\u2010Sapo porphyrites, before (2) magma ascent and crustal extension leading to a different thermal regime around 483 Ma. This article is protected by copyright. All rights reserved.<\/p>\n Ollo de Sapo Cambro-Ordovician volcanics from the Central Iberian basement-A multiphase evolution<\/i>.<\/p>\n Available: https:\/\/www.researchgate.net\/publication\/326401725_Ollo_de_Sapo_Cambro-Ordovician_volcanics_from_the_Central_Iberian_basement-A_multiphase_evolution<\/a> <\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":" Congratulations to team member J\u00fcrgen von Raumer for his latest paper on the Central Iberian basement-A multiphase evolution. The Cambro\u2010Ordovician rhyodacitic to dacitic volcanics from the Central Iberian basement, currently known as Ollo\u2010de\u2010Sapo (toads eye), have been reported as a specific group of felsic porphyritic rocks with blue quartz and large phenocrysts of K\u2010feldspar, in a … Continue reading Central Iberian basement-a multiphase evolution<\/span>