FIRST GEOCHEMICAL AND GEOCHRONOLOGICAL CHARACTERIZATION OF LATE CRETACEOUS MESOSILICIC MAGMATISM IN GASTRE, NORTHERN PATAGONIA, AND ITS TECTONIC RELATION TO OTHER COEVAL VOLCANIC ROCKS IN THE REGION

CLAUDIA BEATRIZ ZAFFARANA; SILVIA LAGORIO; DARÍO ORTS; ALICIA BUSTEROS; DIEGO SILVA NIETO; RAÚL GIACOSA; VÍCTOR RUIZ GONZÁLEZ; BARBARA BOLTSHAUSER; CARLA G. PUIGDOMENECH NEGRE; RUBÉN SOMOZA; MIGUEL HALLER

GEOLOGICAL MAGAZINE

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2017

0016-7568

This work characterizes Late Cretaceous calc-alkaline volcanic rocks in Gastre, in Northern Patagonia, Argentina. These newly found porphyritic rocks bear an 40Ar-39Ar amphibole age of ~74-76 Ma, a subduction-type geochemical signature and a deep, garnet-bearing source. Extruded in a stage of low magmatic activity in the Northern Patagonian Andes (~41-44º S), they could represent an eastward migration of the Late Cretaceous magmatic arc that was associated with a regional Compressive deformational stage in the South American margin.