IANIGLA   20881
INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
artículos
Título:
Finding of two new radiolarian associations calibrated with ammonoids in the Vaca Muerta Formation (Late Jurassic-Early Cretaceous), Neuquen Basin, Argentina
Autor/es:
PUJANA, I.; VENNARI, V.V.
Revista:
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 2017 vol. 75 p. 35 - 50
ISSN:
0895-9811
Resumen:
An association of ammonoids and radiolarians retrieved from a sedimentary section of the Vaca Muerta Formation at Vega de Escalone, Neuquen Basin, Argentina, was analized under a strict stratigraphic control. Nine ammonoid assemblage biozones were identified, indicating an age span from EarlyTithonian to Late Berriasian/earlymost Valanginian for the Vaca Muerta Formation at the studied section. In connection to the ammonoid record, two radiolarian faunas were identified and named J3A1 and J3B1. Fauna J3A1, corresponding to the Virgatosphinctes andesensis Biozone, is dominated by nasellarian generaand represents the first Lower Tithonian radiolarian fauna described from the Neuquén Basin. Fauna J3B1,linked to the interval assigned to the Substeueroceras koeneni Biozone (Late TithonianeEarly Berriasian), yields abundant representatives of the Pantanellid Family. The presence of Complexapora kozuri (Kiessling and Zeiss) and Loopus primitivus (Matsuoka and Yao), two important radiolarian primary markers of the Late Jurassic in North America, supports a Late Tithonian age for at least part of the S. koeneni Biozone in the studied area. Nor certain Berriasian radiolarian faunas nor elements of the Vallupinae Family were identified so far at the Vega de Escalone section.