D.1. Invertebrados del Paleozoico Superior marino de la Cuenca Tepuel-Genoa

TABOADA ARTURO CÉSAR; PAGANI MARÍA ALEJANDRA; PINILLA KARINA; TABOADA CÉSAR AUGUSTO; ROBLES VILCHES ARIANA; PARDO CRISTIAN ADRIÁN

Geología y Recursos Naturales de la Provincia del Chubut

Asociación Geológica Argentina

Lugar: CABA; Año: 2021; p. 643 - 672

The Tepuel-Genoa Basin exhibits an abundant and diverse record of fossil groups, being brachiopods, bivalves, bryozoans and gastropods the most representatives, together with subordinate occurrences of cnidarians, echinoderms, cephalopods, hyolithids, trilobites, ostracods, scaphopods and polyplacophors. Absence of warm-water fossils coupled with several glacial-influenced horizons characterize the Tepuel Group, suggesting its faunal development in cold- to cool-water seas whithin high paleolatitudes (~70° S) and recording the most complete polar view of the Late Paleozoic Ice Age. Plentifull invertebrate fossil remains were reported from the Pampa de Tepuel, Mojón de Hierro and Río Genoa formations, while the Valle Chico and Jaramillo formations have provided scarce records. From base to top the all sequence displays the Globossochonetes faunule in the Valle Chico Formation, the Lanipustula fauna in the lower half of the Pampa de Tepuel Formation and the Verchojania and Languigneotus faunas toward the upper half. The Mojón de Hierro Formation bears the Cimmeriella fauna in its lower half, while the upper part shows the Kochiproductus-Costatumulus fauna. The highest beds of the Mojón de Hierro Formation would be sharing with the lower part of the Río Genoa Formation, the Tivertonia-Costatumulus fauna, while toward the top of the unit appear the Jakutoproductus, Piatnitzkya and Magniplicatina faunas. The whole taxonomic compositional variations evidence a singular faunal identity and a faunistic evolution/change coupled to a variable and dynamic paleobiogeographic linking to western and eastern Gondwana, among other regions.