Paleoenvironmental Evolution of the Restinga of Jurubatiba Lagoons, Rio de Janeiro State
This work analysed assemblages of benthic foraminifera in core samples in lagoons from the Restinga de Jurubatiba Rio de Janeiro State, to observe paleoenvironmental changes and sedimentary deposition processes. Six cores were drilled (vibra-cores) until a depth of 1,56cm, in the Garças, Maria Men...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Universidade Federal do Rio de Janeiro
2017-09-01
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| Series: | Anuário do Instituto de Geociências |
| Subjects: | |
| Online Access: | http://www.anuario.igeo.ufrj.br/2017_3/2017_3_266_280.pdf |
| Summary: | This work analysed assemblages of benthic foraminifera in core samples in lagoons from the Restinga de Jurubatiba
Rio de Janeiro State, to observe paleoenvironmental changes and sedimentary deposition processes. Six cores were drilled
(vibra-cores) until a depth of 1,56cm, in the Garças, Maria Menina, Robalo, Visgueiro, Catingosa and Pires lagoons.
It was found that cores with sandy sediments presented lower abundance and richness of foraminifera species than
fine sediment cores. Through the foraminiferal assemblages, four biofacies were characterized that reflected episodes of
distinct evolutionary conditions for each lagoon. For the sandy lagoons, it was recorded the biofacies Ammonia/ Elphidium
representing moderate marine influence, and the biofacies Aglutinated/Trochammina inflata representing the lagoon
confinement. At the muddy lagoons, occurred the biofacies Ammonia spp./Elphidium spp./Haynesina germanica which
represents paleoenvironments with high marine influence and the biofacies A. tepida/ A. parkinsoniana with low marine
influence that favor conditions to opportunistic species. Radiocarbon dating allowed to record, in the sedimentary
deposition process of the lagoons, Holocene submergence phases related to the marine transgressions |
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| ISSN: | 0101-9759 1982-3908 |