Abstract
The Allen Formation records the first Ingression Atlantic to the Neuquén Basin during the Late Cretaceous. The definition of lithofacies and facies associations interpretation for stratigraphic sections in Paso Córdoba and Salitral Moreno area, Río Negro, Argentina allowed to establish the depositional system that characterized this transgression in the northeastern edge of the Basin. In this paper we present sedimentological analysis of conglomeratic, sandstone, heterolithic and pelitic facies, which allowed the interpretation of tidal channels (TC), intertidal flats (ITF), storms-influenced tidal flat (SITF), subtidal flat (STF) and shoreface deposits (SF) parts of the depositional environment. These deposits represent a sedimentary records preserved example of hybrid systems, in which, the base of the sequence has greater tidal influence, while the upper portion is dominated by wave action. The paleocurrent data indicating a NNW-SSE direction to the shore and correlations and spatial distribution of facies associations propose paleogeographic and paleoenvironmental interpretations to Malargüe Group base. Then in this paper the relationship of this coastal environment presents with wind systems previously defined in this area for the Allen Formation.
Highlights
In this paper we present sedimentological analysis of conglomeratic, sandstone, heterolithic and pelitic facies, which allowed the interpretation of tidal channels (TC), intertidal flats (ITF), stormsinfluenced tidal flat (SITF), subtidal flat (STF) and shoreface deposits (SF) parts of the depositional environment
The correct definition of the depositional environments is an essential component of basin analysis, especially in oil basins where it is of great interest to have detailed sedimentological studies that contribute to regional correlation and characterization of the various units that comprise it, in particular in sections of the stratigraphic column characterized by transitional environments where continuity is highly variable and difficult to predict
The aim of this paper is to present detailed sedimentological study conducted for the Allen Formation by showing the types of paleoenvironments that occurred with the onset of the Atlantic ingression on the eastern edge of the basin, and contribute to the definition of the paleogeography of the Upper Cretaceous
Summary
The correct definition of the depositional environments is an essential component of basin analysis, especially in oil basins where it is of great interest to have detailed sedimentological studies that contribute to regional correlation and characterization of the various units that comprise it, in particular in sections of the stratigraphic column characterized by transitional environments where continuity is highly variable and difficult to predict. The Allen Formation of the Malargüe Group (Fig. 1D) is one of the units that forms the basin’s stratigraphic sequence and, recently, has provided a wide variety of fossils which have been of great interest to paleontological studies. This work contributes to this last aspect and presents the interpretation of the sedimentary system linked to a transitional environment with variations in the influence of tides and the action of waves
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have