Banca de QUALIFICAÇÃO: PEDRO AUGUSTO RODRIGUES FERREIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : PEDRO AUGUSTO RODRIGUES FERREIRA
DATE: 19/12/2023
TIME: 09:00
LOCAL: videoconferência https://www.youtube.com/@ppggufrn
TITLE:

Seismic Moment Tensor for intraplate seismicity in Northeast Brazil

KEY WORDS:

Seismic Moment Tensor; Intraplate Seismicity; Northeast Region

PAGES: 50
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUMMARY:

The genesis of intraplate earthquakes is a question that remains open in seismology. Over the years, several models have been developed with the aim of explaining earthquakes that occur in the interior of continents. Most of them argue that seismic events occur in zones of weakness in the crust or due to the accumulation of intraplate stresses. However, it has been difficult to validate such models due to a paucity in moment tensor solutions. Therefore, determining the stress fields that act inside the plates and characterizing the seismic sources in detail is extremely important to understand the mechanisms that generate such events. Within Brazil, the Northeast region is notorious for its intraplate seismicity. Traditionally, composite focal mechanisms, obtained through the analysis of the first polarities of aftershocks, had been developed for the region. However, these results proved to be inconclusive in confirming intraplate earthquake models proposed for the region. Therefore, the objective of this work is to apply a new methodology to obtain individual focal solutions for seismic events recorded in several seismically active areas of the Northeast region through inversion of spectral amplitudes for P, SH and SV waves with polarity attached. The new results are consistent with the composite focal mechanisms already determined for the Northeast; however, they also demonstrate that a variety of focal solutions can occur within the same seismic zone.

COMMITTEE MEMBERS:
Interno - 1451214 - ADERSON FARIAS DO NASCIMENTO
Interno - 350640 - FRANCISCO HILARIO REGO BEZERRA
Presidente - 1863578 - JORDI JULIA CASAS
Externo à Instituição - MARCELO SOUSA DE ASSUMPÇÃO - USP