Microtremor response of a mass movement in federal district of Brazil
Por:
Hussain Y., Martinez-Carvajal H., Cárdenas-Soto M., Uagoda R., Martino S., Hussain M.B.
Publicada:
1 ene 2017
Resumen:
The present study provides a brief description of the ambient noise recorded at a slow moving mass movement in Ribeirão Contagem Basin. The area is an interesting natural laboratory as river detachment processes in a number of different stages can be identified and are easily accessible. We investigate the site dynamic characteristics of the study area by recording ambient noise time-series at nine points, using portable nine three-component short period seismometers. The time-series are processed to give both horizontal to vertical spectral ratio (HVSR) curves as well as time-frequency plots of noise power spectral density (SPD). The HVSR curves illustrate and quantify aspects of site resonance effects due to underlying geology. Probability density function (PDF) shows that noise level lies well between new high noise model (NHNM) and new lower noise model (NLNM) and their probabilities are higher above 2 Hz. HVSR curves present a uniform lithologically controlled peak at 2 Hz. Directional properties of the wavefield are determined by beamforming method. The f-k analysis results in the E-W component show that at 5 Hz phase velocities are close to 1700 m/s while at 10 Hz dropped to 250 m/s. We observed that between 5 and 16 Hz the incoming wavefield arrive from 260 degrees. Further studies will apply a detailed noise analysis for the understanding of dynamics of the mass movement, which is triggered by the river erosion. © 2017, Universidade Federal do Rio de Janeiro. All rights reserved.
Filiaciones:
Hussain Y.:
University of Brasilia, Department of Civil and Environmental Engineering, SG-12, Asa Norte, Brasilia, DF, Brazil
Martinez-Carvajal H.:
University of Brasilia, Department of Civil and Environmental Engineering, SG-12, Asa Norte, Brasilia, DF, Brazil
National University of Colombia at Medelli´n, Faculty of Mines, Cl. 59a, No. 63-20, Medelli´n, Colombia
Cárdenas-Soto M.:
National Autonomous University of Mexico, Engineering Faculty, Av. Universidad No. 3000, C. U., Coyoacán, Mexico City, Mexico
Uagoda R.:
University of Brasilia, ICC Norte, Brasilia, DF, Brazil
Martino S.:
University of Rome “Sapienza”, Department of Earth Sciences and Research Center on Geological Risks, P.le A. Moro 5, Roma, Italy
Hussain M.B.:
University of Lahore, Gujrat Campus, Department of Physics, Main GT Road, Adjacent Chenab Bridge, Gujrat, Pakistan
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