Suppression of ambient seismic noise in 2D arrays using multichannel Wiener filters

Wang, J. and Tilmann, F. J. and White, R. S. and Soosalu, H. and Bordoni, P. (2007) Suppression of ambient seismic noise in 2D arrays using multichannel Wiener filters. SEG Technical Program Expanded Abstracts, 26 (1). pp. 2654-2658. ISSN 1052-3812 (print) DOI 10.1190/1.2793018

Full text not available from this repository.
Official URL: http://dx.doi.org/10.1190/1.2793018

Abstract

Surface passive monitoring of the microseismic events generated during hydrofracturing is desirable from both scientific and economic perspectives. However, it is challenging because of the small magnitudes of the target events (typically M < 0) and the high level of ambient noise, particularly due to ongoing production and drilling activity, as well as by pumping during hydrofracturing. We present a multi-channel Wiener filtering technique, which allows the removal of coherent noise from sparse 2D arrays without making a priori assumptions about the mode of propagation (e.g., no plane-wave assumption is required for the noise field). We apply this technique to a pilot deployment of 14 three-component seismometers in Wyoming, U.S., which recorded the noise field during hydrofracturing and to a denser array (95 three-component seismometers) located on a landslide in Italy. A detailed analysis of the noise field indicates that the oilfield ambient noise in Wyoming is dominated by ground roll with preferential azimuths at frequencies below 10 Hz. The multi-channel Wiener filter reduces the noise level significantly by up to ~11 dB (at 1 – 6 Hz). Even with this reduction, we failed to detect body waves from events related to fracturing. We estimate that a reduction of ~36 dB would be required to detect the largest fracturing event (M ~ − 1.8) at the Wyoming site using our surface array. However, the application of the multi-channel Wiener filter to selected subsets of the Italian array shows a significant improvement in the signal-noise-ratio (SNR) by ~18 dB (at 6 – 15 Hz) for faint earthquake phases

Item Type: Article
Uncontrolled Keywords: 08AREP IA56 2008 P
Subjects: 02 - Geodynamics, Geophysics and Tectonics
Divisions: 02 - Geodynamics, Geophysics and Tectonics
Journal or Publication Title: SEG Technical Program Expanded Abstracts
Volume: 26
Page Range: pp. 2654-2658
Identification Number: 10.1190/1.2793018
Depositing User: Sarah Humbert
Date Deposited: 16 Feb 2009 13:04
Last Modified: 23 Jul 2013 10:08
URI: http://eprints.esc.cam.ac.uk/id/eprint/785

Actions (login required)

View Item View Item

About cookies