Aeronian (Llandovery, Lower Silurian) palynomorphs and graptolites from the Lipeón Formation, Eastern Cordillera, north-west Argentina |
| |
Authors: | Claudia V. Rubinstein Blanca A. Toro |
| |
Affiliation: | a Departamento de Geología y Paleontología, Unidad de Paleopalinología, CONICET, IANIGLA, CRICyT, Avenida Ruíz Leal s/n, Parque General San Martín, 5500 Mendoza, Argentina b Departamento de Geología y Paleontología, CONICET, IANIGLA, CRICyT. Aveida Ruíz Leal s/n, Parque General San Martín, 5500 Mendoza, Argentina |
| |
Abstract: | The lower levels of the Lipeón Formation, in the Eastern Cordillera, north-west Argentina, yield a marine-dominated palynomorph assemblage, together with graptolites of mid to late mid Llandovery age (Demirastrites convolutus and probably Stimulograptus sedgwickii zones). The palynomorph assemblage is dominated by acritarchs, but also contains algae and terrestrial cryptospores. Crassiangulina variacornuta, considered a potentially good global biostratigraphical marker for the Upper Llandovery is recovered for the first time from the Silurian of Argentina. The occurrence of this species in strata not younger than late Aeronian, and independently dated by graptolites, indicates an early first appearance for Crassiangulina variacornuta, in the Lipeón Formation, below the Aeronian/Telychian boundary. The lower part of the unit corresponds to a quiet marine environment; thus supporting that Crassiangulina variacornuta is a facies-sensitive acritarch. |
| |
Keywords: | Llandovery Acritarchs Cryptospores Graptolites Biostratigraphy Palaeoenvironment |
本文献已被 ScienceDirect 等数据库收录! |
|