Regional scenario of quaternary climatic oscillations: low river terraces in the context of Depressão Periférica and Planalto Ocidental Paulista

Author(s)

Daniel Luís Storani

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Geociências
• Defense date: 2015-08-25

Examining board members

Archimedes Perez Filho; Regina Célia de Oliveira; Salvador Carpi Junior; Emerson Martins Arruda; Marcio Henrique de Campos Zancope

• Advisor: Archimedes Perez Filho

Abstract

Understanding how the climate has presented in recent geomorphological history can elucidate on the way they behave environmental components, especially relief in the face of variations and fluctuations. The São Paulo State, in the geomorphological provinces of Depressão Periférica and Planalto Ocidental Paulista, has river basins where the landforms corresponding to river terraces spread over several kilometers in different contexts. It has been hypothesized that the formation of such river terraces is related to climate oscillations from the end of Pleitosceno to the late Holocene. Dry periods would be responsible for formation of flattened terraces levels, while wetter conditions would be responsible for carving and formation of differences between the cited terraces. This work proposal explores the analysis of low river terraces, which in recent years have been studied with the use of new advanced dating techniques and analysis of soil parent material. The absolute dating through the Optically Stimulated Luminescence (OSL) technique from different points in the context of two geomorphological provinces can confirm the existence of preterit climatic oscillations at regional level, representing progress of geomorphology. Surface coverage (soil parent material) located in low river terraces levels in Atibaia, Capivari, Corumbataí, Itapetininga, Mogi Guaçu, Piracicaba rivers (in Depressão Periférica Paulista context); and Jacaré Guaçu, Jacaré Pepira, Pardo, Peixe, Santo Anastacio, São José dos Dourados, Pardo rivers (in Planalto Ocidental Paulista) were dated, in order to interpret the relationship between ages of these forms and the climatic fluctuations of Quaternary. Particle size and chemical analysis data were also used, in order to interpret the sedimentation conditions of materials and weathering on them. As a result, it is inferred that low river terraces of the two studied geomorphic provinces are the result of a climatic oscilation, drier than the current one, occurred between 1,500 and 1,800 years before the present period (AU)

• FAPESP's process: 11/10285-7 - Regional scenario of Quaternary climatic oscillations: low river terraces in the context of Depressão Periférica and Planalto Ocidental Paulista
• Grantee: Daniel Luis Storani
• Support Opportunities: Scholarships in Brazil - Doctorate