El registro fósil de la Formación Chiquimil y (Mioceno tardío) en el valle de Santa María y su correlato con fauna coetánea en el valle de Villavil-Belén (Catamarca)

MADOZZO JAEN, MA CAROLINA; IBAÑEZ, LUCIA; ORTIZ, PABLO; ARMELLA, MATIAS; NASIF, NORMA; GEORGIEFF, SERGIO; ESTEBAN, GRACIELA

Tucuman

Simposio; IV Simposio Mioceno-Pleistoceno centro-norte de Argentina y XX Congreso Geológico Argentino; 2018

AGA

The Late Miocene-Pliocene sediments outcropping in the high valleys of Tucumán and Catamarca offer an important framework for the understanding of biological and geological- environmental events during this period in the Northwest of Argentina. They are integrated in the San José, Las Arcas, Chiquimil, Andalhuala and Corral Quemado formations. Recent chronological data (absolute data in tuffs and magnetostratigraphy) show a temporary dissociation in the evolution of the intermontane basins. However, the lithostratigraphic units, and hence the faunas they contain, have been directly correlated. Faced with this problem, the fauna of the Chiquimil Formation in the Santa Maria Valley (Catamarca) is reanalyzed from the known registers (Geochelone, Tetrastylus sp. and Tremacyllus cf. diminutus) together with those recently obtained for several localities (Paedotherium, Pseudotypotherium, Stromaphorus, Eosclerocalyptus cf. proximus, large Testudinidae and Chelidae), comparing them with the contemporary associations of the Hualfín-Belén valley. In the Santa María valley, the Chiquimil Formation dates from 6.88 Ma to 6.02 Ma, being contemporaneous with the lower third of the Andalhuala Formation in the Hualfín-Belén Valley. The correlate of vertebrate associations shows differences. This fact may be related to different environmental conditions at the time of sediment deposition in both basins.