Focal Mechanism in Brazil with waveform Modelling

• Grant number: 14/26015-7
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: January 31, 2015
• End date: September 29, 2015
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geophysics
• Principal Investigator: Marcelo Sousa de Assumpção
• Grantee: Fabio Luiz Dias
• Supervisor: Jiří Zahradník
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Charles University (CU), Czech Republic
• Associated to the scholarship: 11/20165-9 - Focal mechanisms and Crustal Stress in Brazil, BP.DR

Abstract

Mapping the stress field in intraplate regions is important to help evaluate models of the plate driving forces and geodynamic properties of the upper mantle. In Brazil, the stress field is poorly known and it has been determined mainly using focal mechanisms, some breakout data and a few in-situ measurements. Recently, with the installation of the Brazilian Seismograph Network, the number of events detected has improved, enabling not only a better knowledge of Brazilian seismicity but also allowing more detailed research on topics such as receiver function, tomography and source studies. This internship has as main objective to improve the number of events with focal mechanism determined such as Miranda (2000), Limeira (1997), Bebedouro (2005-2010) using different techniques like first motion P-wave polarity regional/local, waveform modelling and cyclic scanning of the polarity solutions. The results of this work will be useful for future numerical modeling of global/regional intraplate stress field. Furthermore, the increase of Mw determination will help in seismic hazard in Brazil.