VOLCANISM RELATED TO THE PERMIAN-TRIASSIC TRINITY PENINSULA GROUP, NORTHERN EXTREME OF ANTARCTIC PENINSULA. VOLCANISMO RELACIONADO AL GRUPO TRINITY PENINSULA DEL P�RMICO-TRI�SICO, EXTREMO NORTE DE LA PEN�NSULA ANT�RTICA

ENGLISH:

The Permian-Triassic Trinity Peninsula Group (TPG) forms the mechanical basement of Larsen Basin (del Valle et al. 1992) at the north-eastern extreme of the Antarctic Peninsula. The TPG is virtually barren of palaeontological diagnostic materials at Tabarin and View Point Peninsulas, where the project is proposed. Primary pyroclastic rocks including ignimbrites, peperites and scoria-rich fall deposits alternated with sediments belonging to the TPG were identified at Tabarin and View Point Peninsulas (e.g. Hyden & Tanner 1981, Smellie et al. 1996, Heredia et al. 2004 and 2006, del Valle et al. 2007), but no isotopic age determinations were carried out on such volcanic rocks. Accurate stratigraphic studies and isotopic dating of volcanic rocks included within TPG may provide a tool to determine their real age, as long as the former correlations were carried out mainly on a lithological basis. Additionally, geochemical analyses to be performed on such volcanic rocks may allow the reconstruction of the Early Palaeozoic geotectonic history of the northern Antarctic Peninsula, in the context of Gondwana development.

SPANISH:

El Grupo Trinity Peninsula (GTP) del P�rmico-Tri�sico forma el basamento mec�nico de la Cuenca Larsen (del Valle et al. 1992) en el extremo noreste de la Pen�nsula Ant�rtica. El GTP est� pr�cticamente exento de materiales paleontol�gicos diagn�sticos en las pen�nsulas Tabarin y View Point, donde se propone el proyecto. Rocas pirocl�sticas primarias incluyendo ignimbritas, peperitas y dep�sitos formados por ca�das de escoria volc�nica alternados con sedimentos pertenecientes al GTP fueron identificados en las pen�nsulas Tabarin y View Point (por ejemplo Hyden & Tanner 1981, Smellie et al. 1996, Heredia et al. 2004 y 2006, del Valle et al. 2007), pero no se realizaron determinaciones isot�picas de la edad de estas rocas volc�nicas. Estudios estratigr�ficos y dataciones isot�picas de las volcanitas incluidas en el GTP pueden proveer una herramienta para determinar su edad real, dado que las correlaciones previas fueron hechas principalmente sobre bases litol�gicas. Adicionalmente, an�lisis geoqu�micos ha realizar sobre estas rocas volc�nicas pueden contribuir a la reconstrucci�n de la historia geotect�nica del norte de la Pen�nsula Ant�rtica, en el marco del desarrollo del Gondwana.