Abstract

JANNOU, Gabriel. Paleogene radiolarias from Austral Basin, Tierra del Fuego Island, Argentina. Ameghiniana [online]. 2007, vol.44, n.2, pp.447-466. ISSN 1851-8044.

Two radiolarian assemblages, one from the type locality of the Punta Noguera Formation (near punta Noguera) and the other from the Punta Torcida Formation (cabo Campo del Medio area), both on the Atlantic coast Tierra del Fuego Island, are described and illustrated. The Punta Noguera Formation has been assigned to the Upper Paleocene/lowest Eocene based on its dinocysts and planktonic foraminifers. The occurrence of the index radiolarians Buryella tetradrica Foreman, Amphishaera coronata s.l. (Ehrenberg), Amphishaera goruna (Sanfilippo and Riedel), Mita regina (Campbell and Clark), Theocapsomma erdnussa (Empson-Morin), the abundance of Amphipyndax stocki (Campbell and Clark) and archaeodictyomitrids, and the first appearance of the Microsciadiocapsa? sp. allow us to correlate it with the upper part of the Buryella tetradita Zone of New Zealand, early Late Paleocene in age. The Punta Torcida Formation, considered Early Eocene in age on the basis of its planktonic foraminifers, shares with the Punta Noguera Formation, mostly the same radiolarian species excepting a small number of actinomids and the absence of Microsciadiocapsa? sp. Both assemblages may be reworked.

Keywords : Radiolarios; Argentina; Tierra del Fuego; Paleoceno Superior; Radiolaria; Argentina; Tierra de Fuego; Late Paleocene.