Estacao Agronomica - Bed 6 (Estacao Lmst.): Early Miocene, Brazil

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Bivalvia - Cardiida - Cardiidae
Cardium sp. Linnaeus 1758
Bivalvia - Pectinida - Pectinidae
Pecten agronomica n. sp. Maury 1924
Bivalvia - Pectinida - Anomiidae
see common names

Geography
Country:Brazil State/province:Para
Coordinates: 1.0° South, 48.0° West (view map)
Paleocoordinates:1.4° South, 42.3° West (Wright 2013)
Basis of coordinate:based on nearby landmark
Altitude:1 meters
Geographic resolution:outcrop
Time
Period: Neogene Epoch: Miocene
10 m.y. bin: Cenozoic 5
Key time interval: Early Miocene
Age range of interval: 23.04 - 15.98 m.y. ago
Stratigraphy
Formation:Pirabas Member:Estacao Limestone
Stratigraphic resolution:bed
Stratigraphy comments: Collection from "bed 6" within the limestone unit. No description of the section is given so this collection cannot be placed in a stratigraphic framework. Fauna not very much like that of the Rio Pirabas outcrop, although many species are in common. Molluscan fauna indicate a Lower Miocene age. The deposit is stratigraphically near to the Pirabas Formation, but paleontological evidence is insufficient for an exact correlation. Maury (1924) suggested that it could be synchronous, slightly younger or slightly older. No specimens of Orthaulax have been ound in the fauna, suggesting a younger age, perhaps equivalent to the Gatun Fm. Simone (1994) does not illustrate any other Miocene units in the Parnaiba Basin other than the Pirabas Formation, for which I conclude the Estacao Limestone must now be considered a member of. The Pirabas Fm has a latest Late Oligocene to Middle Miocene age according text. Early Miocene in Vokes (1990), and is accordingly assigned to Early Miocene here.
Lithology and environment
Primary lithology:very fine,shelly/skeletal,gray lithified argillaceous,calcareous marl
Includes fossils?Y
Lithology description: Very fine-grained argillaceous limestone, almost a calcareous clay. Otherwise fine-grained, generally grayish limestone, composed of finely ground sediments, including imperfectly preserved molluscan shells and bryozoan colonies. The limestone is highly calcareous.
Environment:carbonate indet.
Geology comments: No environmental data reported.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Collection methods:selective quarrying,field collection
Reason for describing collection:taxonomic analysis
Collection method comments: Artificial casts of the external molds were made. Collected by F. de Carvalho and Dr. Gonzaga for G. de Campos of the Brazil Geological Survey. Types are reposited at the Museum of the Brazil Geological Survey.
Taxonomic list comments:Fairly lengthy list, but possibly not exhaustive given the quality of the fauna. The nomenclature is antiquated, though has species-resolution assignments; identifications by Maury who had extensive knowledge of circum-Caribbean faunas.
Metadata
Database number:60982
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:A. Hendy Research group:marine invertebrate
Created:2006-05-28 21:50:16 Last modified:2025-02-22 15:12:02
Access level:the public Released:2006-05-28 21:50:16
Creative Commons license:CC0
Reference information

Primary reference:
17560. C. J. Maury. 1924. Fosseis Terciarios Do Brazil. Servico Geologico E Mineralogico Do Brazil Monographia 49 [A. Miller/A. Hendy/P. Wagner]