Banca de QUALIFICAÇÃO: PEDRO AUGUSTO RODRIGUES FERREIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : PEDRO AUGUSTO RODRIGUES FERREIRA
DATA : 26/06/2018
HORA: 09:00
LOCAL: Laboratório sismológico - LabSis
TÍTULO:

Seismic source parameters for intraplate regions of Northeast Brasil

PALAVRAS-CHAVES:

Intraplate seismicity; moment tensor solution; spectral amplitudes; Northeast Brazil

PÁGINAS: 41
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Geociências
RESUMO:

The genesis of intraplate earthquakes remains an open question in seismology. Over the years, several models have been proposed to explain how earthquakes may occur in the interior of continents. Most of them argue that seismic events occur within zones of weakness in the crust, and/or result from the local concentration of tectonic stresses. However, the validation of such models has proven challenging. Thus, constraining the stress field that acts within the plates and characterizing the seismic sources in detail is of extreme importance for improving our understanding of the mechanisms that generate such events. Northeast Brazil is a region of notorious intraplate seismicity. Traditionally, composite focal mechanisms, obtained through analysis of the P-wave polarity of aftershocks, were developed for the region. However, those results were shown to be inconclusive with respect to confirming or rejecting existing models of intraplate seismicity for the region. The objective of this work is to develop deviatoric moment tensor solutions for individual seismic events recorded at several seismically active areas of the Brazilian Northeast, by inverting spectral amplitudes of P, SH and SV waves with polarity attached. Additional source parameters, such a stress drop, are also expected to be determined. The preliminary moment tensor solutions developed so far that are consistent with the composite focal mechanisms determined so far for Northeast Brazil. However, our results demonstrate that a variety of focal mechanisms - rather than a characteristic one – may occur within a given earthquake sequence

MEMBROS DA BANCA:
Presidente - 1863578 - JORDI JULIA CASAS
Interno - 350640 - FRANCISCO HILARIO REGO BEZERRA
Interno - 583.103.478-04 - JOAQUIM MENDES FERREIRA - UFRN