versión ISSN 0002-7014
BLASI, Adriana; PRIETO, Aldo R.; FUCKS, Enrique y FIGINI, Aníbal. Late Pleistocene- Holocene stratigraphic nomenclature and scheme analyses at the Luján River Basin, Buenos Aires, Argentina. Ameghiniana [online]. 2009, vol.46, n.2, pp. 373-390. ISSN 0002-7014.
The sedimentary deposits exposed in cutbanks along the Luján River are considered to be the late Quaternary type locality for geological and paleontological studies of the northeastern Pampas of Argentina. The stratigraphic nomenclatures and sequences proposed for over a century have been used to correlate with sedimentary successions from other regions of Argentina, north of Uruguay and south of Brazil. This long history abounds in mistakes and misinterpretations, and the result is evident in the current stratigraphic nomenclature 'chaos'. In order to understand the stratigraphic meaning and the geochronological placement of the units referring to the late Pleistocene-Holocene period, a critical historical study of the antecedents was carried out, evaluating the meaning of the terms assigned to the different units. The information is organized into three periods: 1847-1920, 1920-1960, and 1995-2005. A geochronometric scale that sets the temporal frame for the continental and marine deposits known as Lujanense, Platense and Querandinense in its type-locality was made. The validity of some of the terms currently in use was analyzed, and the following was proposed: (1) to leave behind the both formal and informal stratigraphic terms in use for the area, (2) to define stratigraphic schemes through the description of depositional units limited by unconformities, their lithofacies and facies differences (3) to carry out numerical dating and, (4) to avoid the creation of stratigraphical nomenclatures that are not in accordance with the current normatives.
Palabras llave : Stratigraphic nomenclature; Late Pleistocene-Holocene; Luján River; Argentina.