1. THE LATE PLEISTOCENE-HOLOCENE RECORD OF
SEA LEVEL IN NORTHEASTERN BRAZIL AND ITS
RELATION TO CLIMATE, EUSTASY AND TECTONICS
Dilce F. Rossetti1, Francisco H. R. Bezerra2, Ana M. Góes3,
Márcio M. Valeriano1, Clódis O. Andrades-Filho1,
Juan C. R. Mittani4, Sonia H. Tatumi4,
Benjamim B. Brito-Neves3
1INPE, 2UFRN, 3USP, 4FATEC

2. Late Quaternary Relative Sea Level
Eustatic fluctuations ice sheets
Late Cretaceous

3. Late Pleistocene-Holocene relative sea level=>climatic fluctuations
Last Interglacial
Holocene Transgression
Younger Dryas
Sea level (m)
Last Glacial Maximum
Age (kyrs B.P.)

4. MAIN PROBLEMS: with basis on data from a few localities
1. Sea level curves have been established
with basis on data from a few localities
2. Chronological data are still insufficient
to identify and correlate events with regional
significance
3. There are many disagreements among
available interpretations

5. 7

6. How passive this passive margin is ?
Is there evidence of paleoseismic activity in the sedimentary record of this region ?

7. RELATIVE SEA LEVEL
EUSTASY
CLIMATE
What about TECTONICS ???

8. Barreiras Formation
(Early/Middle Miocene)

9. BARREIRAS FORMATION- TILTING
Bedding

10. BARREIRAS FORMATION- FAULTS

11. BARREIRAS FORMATION- FAULTS

12. BARREIRAS FORMATION- FAULTS

13. BARREIRAS FORMATION- FOLDS
Barreiras Formation experienced extension and
compression after deposition.

14. Post-Barreiras Sediments
Barreiras Fm.
Post-Barreiras Sediments
Post-Barreiras Sediments
Barreiras Fm.
Barreiras Fm.

15. PB1- Late Pleistocene (OSL) Post-Barreiras Sediments
PB2- Holocene (OSL)

16. POST-BARREIRAS SED.
(PB1)
Sand dike 2m
Convolute beds
Massive bedding

17. POST-BARREIRAS SEDIMENTS- PB1
FAULTED, MASSIVE AND CONVOLUTE BEDDING
Post-Barreiras Sediments
Barreiras Fm.

18. POST-BARREIRAS SED.
(PB1) 2m

20. CONCLUSIONS
Late Pleistocene and Holocene sedimentary deposits (i.e., Post-Barreiras Sediments) are geographically widespread along the NE Brazilian coast;
These strata contain the imprint of relative sea level and of their controlling mechanisms, thus they are of great interest in studies aiming to reconstruct the effect of Late Quaternary sea level changes in Brazil;
The Post-Barreiras Sediments contain a variety of soft sediment deformation structures and massive sands attesting large scale slumps, large scale liquefaction and re-sedimentation , which are mostly due to reactivation of tectonic structures. In addition to generate these seismites within the PBS, this event also deformed the underlying Barreiras Formation;
Tectonics might have played a more important control on relative
Sea level changes in NE Brazil than other factors as eustasy and
climate .

21. CONCLUSIONS
Late Pleistocene and Holocene sedimentary deposits (i.e., Post-Barreiras Sediments) are geographically widespread along the NE Brazilian coast;
These strata are of great interest in studies aiming to reconstruct the effect of Late Quaternary sea level changes in Brazil;
The Post-Barreiras Sediments contain a variety of soft sediment deformation structures and massive sands attesting large scale slumps, large scale liquefaction and re-sedimentation , which are mostly due to reactivation of tectonic structures. In addition to generate these seismites within the PBS, this event also deformed the underlying Barreiras Formation;
Tectonics might have played a more important control on relative
Sea level changes in NE Brazil than other factors as eustasy and
climate .

22. CONCLUSIONS
Late Pleistocene and Holocene sedimentary deposits (i.e., Post-Barreiras Sediments) are geographically widespread along the NE Brazilian coast;
These strata are of great interest in studies aiming to reconstruct the effect of Late Quaternary sea level changes in Brazil;
The Post-Barreiras Sediments contain a variety of soft sediment deformation structures and massive sands attesting large scale slumps, large scale liquefaction and re-sedimentation, which are mostly due to reactivations of tectonic structures;
In addition of generating seismites within the PBS, these events have also deformed the underlying Barreiras Formation;
Tectonics might have played a more important control on relative sea level changes in NE Brazil than other factors as eustasy and climate .

23. CONCLUSIONS
Late Pleistocene and Holocene sedimentary deposits (i.e., Post-Barreiras Sediments) are geographically widespread along the NE Brazilian coast;
These strata are of great interest in studies aiming to reconstruct the effect of Late Quaternary sea level changes in Brazil;
The Post-Barreiras Sediments contain a variety of soft sediment deformation structures and massive sands attesting large scale slumps, large scale liquefaction and re-sedimentation, which are mostly due to reactivations of tectonic structures;
In addition of generating seismites within the PBS, these events have also deformed the underlying Barreiras Formation;
Tectonics might have played a more important control on relative sea level changes in NE Brazil than other factors as eustasy and climate .

24. CONCLUSIONS
Late Pleistocene and Holocene sedimentary deposits (i.e., Post-Barreiras Sediments) are geographically widespread along the NE Brazilian coast;
These strata are of great interest in studies aiming to reconstruct the effect of Late Quaternary sea level changes in Brazil;
The Post-Barreiras Sediments contain a variety of soft sediment deformation structures and massive sands attesting large scale slumps, large scale liquefaction and re-sedimentation, which are mostly due to reactivations of tectonic structures;
In addition of generating seismites within the PBS, these events have also deformed the underlying Barreiras Formation;
Tectonics might have had an important control on relative sea level changes in NE Brazil.