TEMPORAL-SPATIAL SCALE OF NATURAL AND ANTHROPIC PROCESSES RELATED TO THE GENESIS AND EVOLUTION OF ALLUVIAL FANS: HOLOCENIC CLIMATE PULSATIONS AND LAND USE

• Grant number: 22/11563-5
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): March 01, 2023
• Effective date (End): February 28, 2025
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Physical Geography
• Principal Investigator: Archimedes Perez Filho
• Grantee: Mateus Moriconi Prebianca
• Host Institution: Instituto de Geociências (IG). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

The present research proposal is based on the application of the geomorphological approach (relief compartmentation, surface structure of the landscape and morphodynamics), emphasizing discussions about the genesis and spatio-temporal evolution of the Alluvial Fans and the levels of low river and marine terraces that they can cover. The work seeks to understand, compare and associate the genesis of these Alluvial Fans that cover the surfaces of the low fluvial and marine terraces, with Holocene climatic pulsations, in addition, it is assumed that both anthropic and natural processes can be contributing to their formation, but on a different spatial and temporal scale. In this context, the methodological resource adopted to this proposal is based on the systemic method, thus seeking to integrate results obtained through absolute dating, resulting from the application of the Optically Stimulated Luminescence (LOE) method and morphostratigraphic analyzes of the materials involved, from physical laboratory analysis and the use of GeoRadar (GPR) equipment. In this sense, two alluvial fans were identified in the state of Bahia, the first in the interior of the continent, adjacent to the São Desidério river and covering the surface of a low fluvial terrace, while the second is located on the coast, in the region of the Costa do Descobrimento and is associated with cliffs supported by sediments from the Formação Barreiras, possibly covering the surface of marine terraces. The focus of the project is on this second area, considering that in the first area, the collections have already been carried out and can serve as parameters and comparison in the verification of the hypothesis. In this way, it will be possible to identify synchronic and diachronic elements in the genesis of the studied forms, and to analyze the particularities of regional/local environmental dynamics acting at different times.