COMPRESIÓN DEL JURÁSICO INFERIOR EN EL MACIZO DEL DESEADO

CÉSAR NAVARRETE; GUIDO GIANNI

Tucumán

Congreso; XX Congreso Geológico Argentino; 2017

The tectonic context of the Deseado Massif during the beginning of Western Gondwana break-up in Jurassic times has been classically interpreted as related to generalized extension. Based on a structural analysis, we document a Lower Jurassic intraplate contractional stage that affected different sectors of the southern area of the Deseado Massif. The occurrence of contractional structures in Triassic (El Tranquilo Gr.) to Lower Jurassic (Roca Blanca Fm.) sedimentary rocks cross cut by undeformed veins genetically linked to the Lower to Middle Jurassic Bahía Laura Volcanic Complex, plus the presence of a regional scale angular unconformity between the Roca Blanca Fm. and Bahía Laura Volcanic Complex, suggest the existence of a contraccional pulse similar to the one recently described in the San Jorge Gulf Basin.