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Late Quaternary fluvial terrace evolution in the main southern Amazonian tributary. Rossetti D.F.; Cohen M.C.L.; Bertani T.C.; Hayakawa E.H.; Paz J.D.S. 1. The Amazonas drainage basin. Madeira R. 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014. 1.
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Late Quaternary fluvial terrace evolution in the main southern Amazonian tributary Rossetti D.F.; Cohen M.C.L.; Bertani T.C.; Hayakawa E.H.; Paz J.D.S.
1 The Amazonas drainage basin Madeira R. 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
1 The Amazonas drainage basin 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
Anomalous fluvial terraces in the Madeira River 1 Anomalous fluvial terraces in the Madeira River 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
Characteristics of Terrace 1 1 43,000-31,000 cal yrs BP 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
Characteristics of Terrace 2 26,000-14,000 cal yrs BP 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
Characteristics of Terrace 3 1 >12,000-3000 cal yrs BP 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
1 Correlation with global and regional climatic events Fluvial terraces: climatic model 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
1 Tectonic evidence 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
Evidence of neotectonic activity in the region 1 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
Tectonic model for terrace formation Tectonic model for terrace formation Tectonic model for terrace formation Tectonic model for terrace formation Tectonic model for terrace formation Tectonic model for terrace formation 1 Tectonic model for terrace formation Tectonic model for terrace formation Tectonic activity Tectonic activity Tectonic stability 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
1 Tectonic model for terrace formation 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014
CONCLUSIONS 1 • Fluvial terraces of the Madeira River are important archievesfor reconstructing depositional events of one of the main Amazonian tributaries; • -These terraces were formed by a succession of alternating periods of downcutting and sediment aggradation; • However, terrace erosion and deposition cannot be easily accommodated within the context of fluctuating base level linked to climatic events of the Late-Pleistocene-Holocene; • -A model is proposed taking into account fluctuating rates of subsidence promoted by alternating events of fault activity and tectonic quiescence. 19th IAG International Sedimentological Congress- Geneve August 18-22, 2014