Itaboraí Formation
The Itaboraí Formation () is a highly fossiliferous geologic formation and Lagerstätte of the Itaboraí Basin in Rio de Janeiro, southeastern Brazil. The formation reaching a thickness of is the defining unit for the Itaboraian South American land mammal age (SALMA), dating to the Early Eocene, approximately 53 to 50 Ma.

The formation is restricted to the Itaboraí Basin, a minibasin of around the city of Itaboraí, northeast of Rio de Janeiro, and comprises limestones, marls and lignites, deposited in an alluvial to lacustrine environment, dominated by heavy rainfall. The formation overlies Precambrian basement and is overlain by Early Eocene basalts and Late Eocene to Early Oligocene conglomerates.

The up to thick formation has provided many fossil mammals of various groups among which the marsupials and related metatherians dominate, birds, snakes, crocodiles, amphibians, and several species of gastropods. Several genera and species were named after the formation; the marsupials "Itaboraidelphys camposi" and "Carolopaulacoutoia itaboraiensis", the birds "Itaboravis elaphrocnemoides", "Eutreptodactylus itaboraiensis" and "Eutreptodactylus itaboraiensis", the snake "Itaboraiophis depressus" and crocodile "Eocaiman itaboraiensis" and the gastropods "Itaborahia lamegoi", "Biomphalaria itaboraiensis" and "Gastrocopta itaboraiensis".

The formation is the richest Cenozoic fossiliferous formation of Brazil, leading to the establishment of the "Parque Paleontológico de São José de Itaboraí" ("São José de Itaboraí Paleontological Park") in 1995. The site is a candidate for becoming a UNESCO World Heritage Site.
None
fossiliferous
UNK
Q736917
formation
Concept
Q2122699
Lagerstätte
LOC
None
Itaboraí Basin
UNK
Q41428
Rio de Janeiro
LOC
Q155
Brazil
LOC
Q6092292
Itaboraian
TIME
Q5817530
South American land mammal age
Concept
Q76274
Early Eocene
TIME
None
Itaboraí Basin
UNK
Q841244
Itaboraí
LOC
Q8678
Rio de Janeiro
LOC
Q23757
limestone
Concept
Q184053
marl
Concept
Q156267
lignite
Concept
Q6185405
alluvial
Concept
Q23397
lacustrine
Concept
Q1994702
environment
UNK
Q103910
Precambrian
TIME
Q2143968
basement
Concept
Q43338
basalt
Concept
Q191704
conglomerates
Concept
Q7377
mammal
Concept
Q5113
bird
Concept
Q2102
snake
Concept
Q2535664
crocodile
Concept
Q10908
amphibian
Concept
Q4867740
gastropod
Concept
None
Itaboraidelphys camposi
UNK
None
Carolopaulacoutoia itaboraiensis
UNK
Q583703
Itaboravis elaphrocnemoides
Concept
Q55643017
Eutreptodactylus itaboraiensis
MISC
Q55643017
Eutreptodactylus itaboraiensis
MISC
None
Itaboraiophis depressus
UNK
Q5381601
Eocaiman itaboraiensis
Concept
None
Itaborahia lamegoi
UNK
None
Biomphalaria itaboraiensis
UNK
None
Gastrocopta itaboraiensis
UNK
Q7809
UNESCO
Concept
Q9259
World Heritage Site
EVE
Q85770263
Itaboraí Formation
UNK
1995-01-01T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
1995
DATE
+53^^http://www.w3.org/2001/XMLSchema#decimal
53
NUMBER
+50^^http://www.w3.org/2001/XMLSchema#decimal
50
NUMBER
country
instance of
maintained by