Advanced

A numerical comparison of 2D resistivity imaging with 10 electrode arrays

Dahlin, Torleif LU and Zhou, Bing (2004) In Geophysical Prospecting 52(5). p.379-398
Abstract
Numerical simulations are used to compare the resolution and efficiency of 2D resistivity imaging surveys for 10 electrode arrays. The arrays analysed include pole-pole (PP), pole-dipole (PD), half-Wenner (HW), Wenner-alpha (WN), Schlumberger (SC), 'dipole-dipole (DD), Wenner-beta (WB), gamma-array (GM), multiple or moving gradient array (GD) and mid point-potential-referred measurement (MPR) arrays. Five synthetic geological models, simulating a buried channel, a narrow conductive dike, a narrow resistive dike, dipping blocks and covered waste ponds, were used to examine the surveying efficiency (anomaly effects, signal-to-noise ratios) and the imaging capabilities of these arrays. The responses to variations in the data density and noise... (More)
Numerical simulations are used to compare the resolution and efficiency of 2D resistivity imaging surveys for 10 electrode arrays. The arrays analysed include pole-pole (PP), pole-dipole (PD), half-Wenner (HW), Wenner-alpha (WN), Schlumberger (SC), 'dipole-dipole (DD), Wenner-beta (WB), gamma-array (GM), multiple or moving gradient array (GD) and mid point-potential-referred measurement (MPR) arrays. Five synthetic geological models, simulating a buried channel, a narrow conductive dike, a narrow resistive dike, dipping blocks and covered waste ponds, were used to examine the surveying efficiency (anomaly effects, signal-to-noise ratios) and the imaging capabilities of these arrays. The responses to variations in the data density and noise sensitivities of these electrode configurations were also investigated using robust (L-1-norm) inversion and smoothness-constrained least-squares (L-2-norm) inversion for the five synthetic models. The results show the following. (i) GM and WN are less contaminated by noise than the other electrode arrays. (ii) The relative anomaly effects for the different arrays vary with the geological models. However, the relatively high anomaly effects of PP, GM and WB surveys do not always give a high-resolution image. PD, DD and GD can yield better resolution images than GM, PP, WN and WB, although they are more susceptible to noise contamination. SC is also a strong candidate but is expected to give more edge effects. (iii) The imaging quality of these arrays is relatively robust with respect to reductions in the data density of a multi-electrode layout within the tested ranges. (iv) The robust inversion generally gives better imaging results than the L2-norm inversion, especially with noisy data, except for the dipping block structure presented here. (v) GD and MPR are well suited to multichannel surveying and GD may produce images that are comparable to those obtained with DD and PD. Accordingly, the GD, PD, DD and SC arrays are strongly recommended for 2D resistivity imaging, where the final choice will be determined by the expected geology, the purpose of the survey and logistical considerations. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Geophysical Prospecting
volume
52
issue
5
pages
379 - 398
publisher
EAGE / Wiley
external identifiers
  • wos:000223644000002
  • scopus:4444332792
ISSN
1365-2478
DOI
10.1111/j.1365-2478.2004.00423.x
language
English
LU publication?
yes
id
95f765c9-33de-45a7-bf9d-d53b8edba2b7 (old id 268576)
date added to LUP
2007-08-02 12:05:34
date last changed
2017-10-08 03:34:19
@article{95f765c9-33de-45a7-bf9d-d53b8edba2b7,
  abstract     = {Numerical simulations are used to compare the resolution and efficiency of 2D resistivity imaging surveys for 10 electrode arrays. The arrays analysed include pole-pole (PP), pole-dipole (PD), half-Wenner (HW), Wenner-alpha (WN), Schlumberger (SC), 'dipole-dipole (DD), Wenner-beta (WB), gamma-array (GM), multiple or moving gradient array (GD) and mid point-potential-referred measurement (MPR) arrays. Five synthetic geological models, simulating a buried channel, a narrow conductive dike, a narrow resistive dike, dipping blocks and covered waste ponds, were used to examine the surveying efficiency (anomaly effects, signal-to-noise ratios) and the imaging capabilities of these arrays. The responses to variations in the data density and noise sensitivities of these electrode configurations were also investigated using robust (L-1-norm) inversion and smoothness-constrained least-squares (L-2-norm) inversion for the five synthetic models. The results show the following. (i) GM and WN are less contaminated by noise than the other electrode arrays. (ii) The relative anomaly effects for the different arrays vary with the geological models. However, the relatively high anomaly effects of PP, GM and WB surveys do not always give a high-resolution image. PD, DD and GD can yield better resolution images than GM, PP, WN and WB, although they are more susceptible to noise contamination. SC is also a strong candidate but is expected to give more edge effects. (iii) The imaging quality of these arrays is relatively robust with respect to reductions in the data density of a multi-electrode layout within the tested ranges. (iv) The robust inversion generally gives better imaging results than the L2-norm inversion, especially with noisy data, except for the dipping block structure presented here. (v) GD and MPR are well suited to multichannel surveying and GD may produce images that are comparable to those obtained with DD and PD. Accordingly, the GD, PD, DD and SC arrays are strongly recommended for 2D resistivity imaging, where the final choice will be determined by the expected geology, the purpose of the survey and logistical considerations.},
  author       = {Dahlin, Torleif and Zhou, Bing},
  issn         = {1365-2478},
  language     = {eng},
  number       = {5},
  pages        = {379--398},
  publisher    = {EAGE / Wiley},
  series       = {Geophysical Prospecting},
  title        = {A numerical comparison of 2D resistivity imaging with 10 electrode arrays},
  url          = {http://dx.doi.org/10.1111/j.1365-2478.2004.00423.x},
  volume       = {52},
  year         = {2004},
}