Neuquén Group

The Neuquén Group is a group of geologic formations found in Argentina. Rocks in the Neuquén Group fall within the Cenomanian to early Campanian stages of the Late Cretaceous Period. It overlies the older Lohan Cura Formation and is itself overlain by the younger Allen Formation of the Malargüe Group, separated from both by unconformities, dated to 98 and 79 Ma respectively.

Description

Deposits have been located in the provinces of Río Negro, Neuquén, and Mendoza. Although several different types of environments are represented in various sections of the Neuquén Group, the dominant regime is alluvial deposition. Many dinosaur and other fossil types have been discovered in these sediments.

Subdivision

There are seven formations within the Neuquén Group. These are divided into three subgroups named after major rivers in the area. In some works, the subgroups themselves are treated as formations and what usually is considered to be the formations as mere members of these. However, particularly in the Río Limay Subgroup, the formations are clearly composed of very distinct rock layers.
Neuquén Group strata, ordered from youngest to oldest

South of Añelo, on the road between Lake Los Barreales and the Neuquén River are views on the successively younger formations, starting with the Lisandro Formation to the northwest of Lake Los Barreales, and finally crossing the Anacleto Formation about down the road near the eastern tip of the lake. The older strata are exposed south of Lake Los Barreales.