STRATIGRAPHY AND RADAR-FACIES OF THE TRANSITION BETWEEN TRANSGRESSIVE AND REGRESSIVE PHASES IN COASTAL HOLOCENE OF SOUTHERN SANTA CATARINA

• Grant number: 11/22671-9
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: April 01, 2012
• End date: May 31, 2013
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Paulo César Fonseca Giannini
• Grantee: Milene Fornari
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

This project is a continuation of the doctoral research carried out by the candidate with scholarship FAPESP (2007-2010) intitled "Sedimentary evolution of the backbarrier in Jaguaruna-Laguna, Santa Catarina". The aim of the postdoctoral research is to identify the depositional architecture in the sedimentary record of the transition between transgressive and regressive phases of this Holocene coastal region, through the integration of seismic data with previous results of stratigraphic and chronological analysis. To achieve this goal, we acquired 200 km of GPR (Ground Penetrating Radar) sections, parallel and perpendicular to the coastline, with antennas of 70 MHz, 100 MHz and 200 MHz, covering all the different areas of the barrier-backbarrier complex. The GPR sections will be processed and interpreted using the methods of radar stratigraphy adapted from seismic-reflection. In the interpretation radar-sequences will be identified by recognition of types of stratal termination, and radar-facies will be determined based on geometric patterns and external configuration (shape, dep, continuity) of the reflectors. The geophysical results will be interpreted by combining the GPR profile of each section with previous data analysis and dating of sedimentary facies. This integration will allow registering the transition between the transgressive and regressive depositional coastal systems, and discussing the chronological meaning of the bounding surfaces associated with it (ravines and / or maximum flood), a subject of little discussion in Holocene sedimentary deposits around the world.