Artículos de revistas
The 2009 earthquake, magnitude m(b) 4.8, in the Pantanal Wetlands, west-central Brazil
Fecha
2016-09-01Registro en:
Anais Da Academia Brasileira De Ciencias. Rio Janeiro: Acad Brasileira De Ciencias, v. 88, n. 3, p. 1253-1264, 2016.
0001-3765
10.1590/0001-3765201620140507
WOS:000383340200009
Autor
Universidade de São Paulo (USP)
Universidade Federal de Mato Grosso do Sul (UFMS)
Universidade de Brasília (UnB)
Universidade Estadual Paulista (Unesp)
Institución
Resumen
The main goal of this paper is to characterize the Coxim earthquake occurred in June 15th, 2009 in the Pantanal Basin and to discuss the relationship between its faulting mechanism with the Transbrasiliano Lineament. The earthquake had maximum intensity MM V causing damage in farm houses and was felt in several cities located around, including Campo Grande and Goiania. The event had an m(b) 4.8 magnitude and depth was 6 km, i.e., it occurred in the upper crust, within the basement and 5 km below the Cenozoic sedimentary cover. The mechanism, a thrust fault mechanism with lateral motion, was obtained by P-wave first-motion polarities and confirmed by regional waveform modelling. The two nodal planes have orientations (strike/dip) of 300 degrees/55 degrees and 180 degrees/55 degrees and the orientation of the P-axis is approximately NE-SW. The results are similar to the Pantanal earthquake of 1964 with m(b) 5.4 and NE-SW compressional axis. Both events show that Pantanal Basin is a seismically active area, under compressional stress. The focal mechanism of the 1964 and 2009 events have no nodal plane that could be directly associated with the main SW-NE trending Transbrasiliano system indicating that a direct link of the Transbrasiliano with the seismicity in the Pantanal Basin is improbable.