Guichón Formation | |
---|---|
Stratigraphic range:
Aptian-
Santonian ~ | |
Type | Geological formation |
Unit of | Paysandú Group |
Underlies | Mercedes Formation |
Overlies | Arapey Formation |
Thickness | Up to >100 m (330 ft) (in wells) |
Lithology | |
Primary | Sandstone |
Other | Conglomerate |
Location | |
Coordinates | 32°00′S 57°42′W / 32.0°S 57.7°W |
Approximate paleocoordinates | 38°24′S 30°00′W / 38.4°S 30.0°W |
Region | Paysandú Department |
Country | Uruguay |
Extent | Norte Basin |
Type section | |
Named for | Guichón |
The Guichón Formation is a Late Cretaceous geologic formation of the Paysandú Group in Uruguay. Dinosaur remains are among the fossils that have been recovered from the formation. [1]
The Guichón Formation comprises mainly pink-greyish to reddish sandstones, which contain moderate to well-sorted, subrounded, fine to medium-sized grains in a pelitic matrix. These sandstones (which compositionally are feldspathic wackes) are either massive or may instead exhibit parallel lamination, cross-lamination and graded bedding. These lithologies were deposited in southwest-trending alluvial– fluvial systems comprising low-sinuosity channels traversing through sandy plains. Subordinate to the already mentioned sandstones are conglomeratic and pelitic lithologies, interpreted as channel-fill and overbank deposits, respectively. It is inferred that the Guichón Formation was deposited in warm, semi-arid climatic conditions. [2] The formation has been correlated to the Puerto Yeruá Formation of northwestern Argentina. [3]
The formation reaches a thickness of more than 100 metres (330 ft) in wells perforating the formation. [4] It is overlain by the Mercedes Formation and overlies the Arapey Formation. [5]
The following fossils have been reported from the formation: [2] [6]
Guichón Formation | |
---|---|
Stratigraphic range:
Aptian-
Santonian ~ | |
Type | Geological formation |
Unit of | Paysandú Group |
Underlies | Mercedes Formation |
Overlies | Arapey Formation |
Thickness | Up to >100 m (330 ft) (in wells) |
Lithology | |
Primary | Sandstone |
Other | Conglomerate |
Location | |
Coordinates | 32°00′S 57°42′W / 32.0°S 57.7°W |
Approximate paleocoordinates | 38°24′S 30°00′W / 38.4°S 30.0°W |
Region | Paysandú Department |
Country | Uruguay |
Extent | Norte Basin |
Type section | |
Named for | Guichón |
The Guichón Formation is a Late Cretaceous geologic formation of the Paysandú Group in Uruguay. Dinosaur remains are among the fossils that have been recovered from the formation. [1]
The Guichón Formation comprises mainly pink-greyish to reddish sandstones, which contain moderate to well-sorted, subrounded, fine to medium-sized grains in a pelitic matrix. These sandstones (which compositionally are feldspathic wackes) are either massive or may instead exhibit parallel lamination, cross-lamination and graded bedding. These lithologies were deposited in southwest-trending alluvial– fluvial systems comprising low-sinuosity channels traversing through sandy plains. Subordinate to the already mentioned sandstones are conglomeratic and pelitic lithologies, interpreted as channel-fill and overbank deposits, respectively. It is inferred that the Guichón Formation was deposited in warm, semi-arid climatic conditions. [2] The formation has been correlated to the Puerto Yeruá Formation of northwestern Argentina. [3]
The formation reaches a thickness of more than 100 metres (330 ft) in wells perforating the formation. [4] It is overlain by the Mercedes Formation and overlies the Arapey Formation. [5]
The following fossils have been reported from the formation: [2] [6]