Reorganization of the Western Amazon drainage system during the Neogene and Quaternary based on the provenance of sediments solved by luminescence techniques

• Grant number: 21/14022-2
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): September 01, 2022
• Effective date (End): August 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal researcher: Fabiano Do Nascimento Pupim
• Grantee: Priscila Emerich Souza
• Home Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil
• Associated research grant: 18/23899-2 - Trans-Amazon Drilling Project: origin and evolution of the forests, climate, and hydrology of the South American tropics, AP.PFPMCG.TEM

Abstract

The formation and reorganization of Amazon fluvial systems has been widely discussed regarding its role in the promotion of the Amazonian biodiversity. In order to better understand the landscape evolution and, thus, to reconstruct the palaeoceanographic history of the Amazon drainage, it is crucial to have information about the sediments provenance associated to the depositional ages of its main river systems. New dating data has broadened the knowledge on the chronology of the fluvial deposits on the West and Central Amazon, however little is known about the provenance of sediments. Recently it has been demonstrated the potential in applying Optical Stimulated Luminescence (OSL) techniques in sediments provenance studies because of the properties of the signal inherited from the rock-source, the weathering conditions, and the transport and depositional history of the sediments. The objectives of this research include characterizing the sensitivity (i.e. the light intensity per dose per mass) of quartz and feldspar luminescence signals, characterizing the relative contribution of quartz signal components (i.e. fast, medium, and slow), and investigating the mechanisms that promote the OSL signal sensitization. Sediment samples from key areas over West Amazon will be studied, including samples from riverbeds, fluvial terraces, and deep gravity cores. The OSL data will be complemented with major elements analysis, environmental magnetism data, and will be associated with depositional ages obtained within this project or in previous published works. This proposal is linked to the thematic project "Trans-Amazon Drilling Project", funded by FAPESP (process 2018/23899-2), which will recover deep cores over Amazon in order to investigate how physical changes in the landscape contributed to the Amazonian biodiversity promotion. (AU)