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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Relaxation time distribution obtained from a Debye decomposition of spectral induced polarization data

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Author(s):
Ustra, Andrea [1] ; Mendonca, Carlos Alberto [1] ; Ntarlagiannis, Dimitrios [2] ; Slater, Lee D. [2]
Total Authors: 4
Affiliation:
[1] Univ Sao Paulo, Dept Geophys, Sao Paulo - Brazil
[2] Rutgers Newark, Dept Earth & Environm Sci, Newark, NJ - USA
Total Affiliations: 2
Document type: Journal article
Source: GEOPHYSICS; v. 81, n. 2, p. E129-E138, MAR-APR 2016.
Web of Science Citations: 6
Abstract

We have developed an alternative formulation for Debye decomposition of complex electric conductivity spectra, by recasting it into a new set of parameters with a close relationship to the continuous formulation for the complex conductivity method. The procedure determines a relaxation time distribution (RTD) and two frequency-independent parameters that modulate the complex conductivity spectra. These two parameters represent (1) the direct current contribution and (2) the conductivity range spanned by the low-and high-frequency limits. The distribution of relaxation times quantifies the contribution of each distinct relaxation process. Assuming that characteristic times with insignificant contributions can be ignored, a minimum set of characteristic relaxation times is determined. Each contribution can then be associated with specific polarization processes that can be interpreted in terms of electrochemical or interfacial parameters of mechanistic models derived from inverted parameters obtained from the proposed approach. Synthetic tests show that the procedure can fit spectral induced polarization (SIP) data and successfully retrieve the RTD. We have applied the procedure to laboratory SIP data from experiments with sand and oil mixtures undergoing microbial degradation of hydrocarbons. The RTD reveals evidence of a length scale at which a new polarization process takes place as a result of the biodegradation process. (AU)

FAPESP's process: 13/22165-1 - Compact inversion of induced polarization spectrum
Grantee:Andréa Teixeira Ustra
Support Opportunities: Scholarships in Brazil - Post-Doctoral