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Sammanfattning
This paper presents an advanced signal processing schemefor timedomain induced polarization full waveform data.The scheme includes several steps with an improvedinduced polarization (IP) response gating design usingconvolution with tapered windows to suppress highfrequency noise, a logarithmic gate width distribution foroptimizing IP data quality and an estimate of gatinguncertainty. Additional steps include modelling andcancelling of nonlinear background drift and harmonicnoise and a technique for efficiently identifying andremoving spikes. The cancelling of nonlinear backgrounddrift is based on a ColeCole model which effectivelyhandles current induced electrode polarization drift. Themodelbased cancelling of harmonic noise reconstructs theharmonic noise as a sum of harmonic signals with acommon fundamental frequency. After segmentation ofthe signal and determining of noise model parameters foreach segment, a full harmonic noise model is subtracted.Furthermore, the uncertainty of the background driftremoval is estimated which together with the gatinguncertainty estimate and a uniform uncertainty gives atotal, datadriven, error estimate for each IP gate. Theprocessing steps is successfully applied on full field profiledata sets. With the modelbased cancelling of harmonicnoise, the first usable IP gate is moved one decade closerto time zero. Furthermore, with a ColeCole backgrounddrift model the shape of the response at late times isaccurately retrieved. In total, this processing schemeachieves almost four decades in time and thus doubles theavailable spectral information content of the IP responsescompared to the traditional processing.
Originalspråk  engelska 

Titel på värdpublikation  Proceedings of the 4th international workshop on induced polarization 
Sidor  14 
Antal sidor  4 
Status  Published  2016 juni 8 
Ämnesklassifikation (UKÄ)
 Geofysik
 Signalbehandling
Fingeravtryck
Utforska forskningsämnen för ”Doubling the spectrum of timedomain induced polarization: removal of nonlinear selfpotential drift, harmonic noise and spikes, tapered gating, and uncertainty estimation”. Tillsammans bildar de ett unikt fingeravtryck.Projekt
 1 Avslutade

TRUST 2.1: Geoelectrical Imaging for Site Investigation for Urban Underground Infrastructure
Dahlin, T., Olsson, P., Johansson, S., Rossi, M., Sparrenbom, C., Rosqvist, H., Auken, E., Fiandaca, G., Svensson, M., Hagerberg, D., Hedblom, P. & Bastani, M.
2012/01/01 → 2018/12/31
Projekt: Forskning
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