Banca de QUALIFICAÇÃO: JOSÉ AUGUSTO SILVA DA FONSÊCA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : JOSÉ AUGUSTO SILVA DA FONSÊCA
DATA : 18/06/2019
HORA: 09:00
LOCAL: Auditório do departamento de geofísica
TÍTULO:

Recent seismicity in Cascavel-CE in 2017

PALAVRAS-CHAVES:

Intraplate seismicity; local network; focal mechanism

PÁGINAS: 30
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Geociências
RESUMO:

Northeast Brazil is one of the most seismic regions of Brazil. The Cascavel area, located in the Ceará state, was been hit by a 5.2 m_b event in 1980, the biggest earthquake that occurred in Brazil northeast, and seismicity in this area was significantly higher for at least the next decade. After this period, seismicity in the region decayed. In 2017, seismicity in the region was reported again with many events with magnitude 3.0 m_R. During the period of 24^th March 2017 until 12^th December 2017, we were able to deploy a portable digital seismographic network in the region.  The network was composed of five short period sensors and one broad band sensor and we were able to estimate the hypocentral location and invert for composite focal mechanism. Preliminary results show that 980 seismic events were identified, and 240 were recorded in at least 3 stations and, therefore were useful for our inversion of the hypocentral location.  The depths obtained are typically in the range of 4 to 8 km. Most of the focal mechanisms P-axis direction appears to be roughly parallel to the coastline, what is expected for Northeast Brazil, indicating a strong influence of north marginal coast Brazilian in local stress field. Furthermore, focal mechanisms indicate too a possible strike-slip with sinistral movement fault segment (approximately 30 km extension).

MEMBROS DA BANCA:
Presidente - 583.103.478-04 - JOAQUIM MENDES FERREIRA - UFRN
Interno - 1451214 - ADERSON FARIAS DO NASCIMENTO
Externo à Instituição - HELENO CARLOS DE LIMA NETO - UnP