A multi-electrode array for resistivity surveying

Griffiths, D. H.; Turnbull, John

doi:10.3997/1365-2397.1985013

Cited by 111 publications

(52 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some authors consider that the Wenner array is most sensitive to changes in the vertical resistivity of the subsoil (Griffiths and Turnbull, 1985;Griffiths and Barker, 1993), the average reliable depth for investigation being around half that of the spacing (Edwards, 1977). Because it has a small geometric factor, leads to a strong signal even in areas with electromagnetic background noise.…”

Section: Methodsmentioning

confidence: 99%

Electrical Tomography Applied to the Detection of Subsurface Cavities

Martines-López¹,

Rey²,

Dueñas³

et al. 2013

JCKS

View full text Add to dashboard Cite

Abstract:We have analyzed the geoelectric response produced by three cavities cut into different geological substrata of granite, phyllite, and sandstone that had previously been characterized by direct methods. We also examined a mining void excavated in granite. In each case, we applied three different geoelectric arrays (Wenner-Schlumberger, Wenner and dipole-dipole) and several inter-electrode spacings. The survey results suggest that electrical resistivity tomography is a viable geophysical tool for the detection and monitoring of mining voids and other subsurface cavities. The results vary depending on a wide range of factors, such as the depth and diameter of the cavity, the multi-electrode array used, the inter-electrode spacing, the geological model, and the density of the data. The resolution capacity of the Wenner-Schlumberger array for the detection of these cavities was greater than that of the Wenner array and slightly better than the dipole-dipole. There is a direct relationship between inter-electrode spacing and diameter of the cavity. In general, we observed a loss of resolution as the distance between the electrodes increased. The most efficient detection was achieved when the inter-electrodes distance was less than or equal to the diameter of the cavity itself. In addition, cavity detection became increasingly less precise with its depth beneath the surface. Cavities with a radius of about 1.5 m were located by both the WennerSchlumberger method and the dipole-dipole at depths of more than 4.6 m, which means that prospecting can be carried out at depths 3 times the radius of the cavity.

show abstract

Section: Methodsmentioning

confidence: 99%

Electrical Tomography Applied to the Detection of Subsurface Cavities

Martines-López¹,

Rey²,

Dueñas³

et al. 2013

JCKS

View full text Add to dashboard Cite

show abstract

“…Improvement in resistivity methods using multi-electrode arrays has led to an important development in electrical imaging for subsurface surveys (Barker 1978;Griffiths and Turnbull 1985;Griffiths et al 1990;Barker 1992;Griffiths and Barker 1993). Such surveys are usually carried out using a large number of electrodes connected through a multi-core cable.…”

Section: Electrical Resistivity Imaging (Eri) Methodsmentioning

confidence: 99%

Integrated studies for characterization of lineaments used to locate groundwater potential zones in a hard rock region of Karnataka, India

et al. 2006

View full text Add to dashboard Cite

An integrated study was carried out to investigate the subsurface geological conditions in a hard rock environment, with the aim of identifying zones with groundwater resource potential. The study, in Bairasagara watershed, Karnataka, India, considered geomorphology, water level, resistivity imaging, self potential, total magnetic field and susceptibility. The signatures due to lineaments have been clearly identified and their role in groundwater movement has been documented. Synthetic simulation methods were used to model the electrical response of the lineament using finite differential modeling scheme. The inverted image of the field data is compared with the synthetic image and iteration were performed on the initial model until a best match was obtained resulting on the generation of the calibrated resistivity image of the subsurface. Resistivity imaging revealed that the dykes are weathered/fractured to a depth of 6-8 m and are compact at deeper levels, and that they behave as barriers to groundwater movement, yet facilitate a good groundwater potential zone on the upgra- dient side. The results of magnetic surveys were utilized in differentiating granites and dolerite dykes with an insignificant resistivity contrast. Geomorphological expression alone cannot reveal the groundwater potential associated with a lineament. However, characterizing the nature of the feature at depth with integrated geophysical methods provides essential information for assessing that potential.Résumé Uneétude aété réalisée sur la géologique de sub-surface en milieu rocheux fracturé, avec pour objectif l'identification des zones possédant des potentiels de ressource en eau souterraine. Cetteétude, sur le bassin versant de Bairasagara, Karnataka, prend en compte la géomorphologie, le niveau de l'eau, les images de résistivité, le self potentiel, le champ magnétique total et la susceptibilité. Les signaux dusà la présence de linéaments, ontété clairement identifiés ainsi que leur influence sur le mouvement des eaux souterraines. Les méthodes de simulation synthétique ontété utilisées pour modéliser la réponsé electrique des linéaments, en utilisant une modélisation par différences finies. L'image inversée des données de terrain est comparée avec l'image synthétique; des itérations sur le modèle initial ontété mises en oeuvre jusqu'à un rapprochement optimal, résultant en la génération d'une image calibrée de la résistivité de la sub-surface. Les images de résistivités révèlent que les dykes sont altérés et fracturés sur une profondeur de 6à 8 mètres et sont compactésà des profondeurs plus importantes. Les dykes se conduisent dés lors comme des barrières au mouvement des eaux souterraines. Cependant ils favorisent un bon potentiel, du point de vue de la remontée des gradients. Les résultats des levés magnétiques ontété utilisés pour différencier les dykes de granite et les dykes de dolérite avec des contrastes de résistivité trop faibles. L'étude géomorphologique seule n'aurait pu suffireà comprendre le potentiel des eaux s...

show abstract

“…2b). The measurements are based on the Wenner geometry proposed by Griffiths and Turnbull (1985) and Griffiths et al (1990). A 4-point light 10 W high-resolution induced polarization earth resistivity meter (Lippmann Geophysical Instruments) with 60 active electrodes and an electrode spacing of 2.5 m for line RT1, 5 m for profile RT2 and 6 m for RT3 was used.…”

Section: Electrical Resistivity Tomography (Ert)mentioning

confidence: 99%

Quaternary evolution of the inner Riss Valley, Tyrol (Austria) – an integrated sedimentological and geophysical case study

Mair¹,

Chwatal²,

Reimer³

et al. 2016

AJES

View full text Add to dashboard Cite

We present the results of a study examining Quaternary sediments in the central and inner Riss Valley of the Karwendel Mountains, Tyrol. By using geological mapping, seismic and geoelectrical surveys, as well as shallow drilling and radiocarbon dating we investi gated the sedimentary evolution of this previously poorly studied area. At Großer Ahornboden, seismic data reveal a glacially carved bedrock surface, buried beneath up to 140 m of sediments. The lowest sediment sequence consists of consolidated sediments showing high seismic velocities (2750 m/s) and reaching a thickness of 115 m. The overlying uncompacted sequence yielded lower velocity values (500 to 1100 m/s) and is interpreted as Holocene valley fill, with sediment derived from Rissbach river, small talus screes and debris-flow fans from tributary creeks. Up to 10-m-thick deposits of a Holocene paleolake, dammed by a large Lateglacial terminal moraine ridge, are present at the northern rim of Großer Ahornboden. Radiocarbon dates constrain the duration of this lake to between 10.5-10.2 and 5.5-5.3 cal ka BP. Lacustrine sediments pinch out in the subsurface just below the small fan leading down from Tränkkarl. In the central Riss Valley over 100 m thick, consolidated sediments of a proglacial delta are exposed. This delta complex consists of bottomset silts and thick foreset gravel and is overlain by diamict forming poorly developed moraine ridges of Lateglacial origin.

show abstract

A multi-electrode array for resistivity surveying

Cited by 111 publications

References 0 publications

Electrical Tomography Applied to the Detection of Subsurface Cavities

Electrical Tomography Applied to the Detection of Subsurface Cavities

Integrated studies for characterization of lineaments used to locate groundwater potential zones in a hard rock region of Karnataka, India

Quaternary evolution of the inner Riss Valley, Tyrol (Austria) – an integrated sedimentological and geophysical case study

Contact Info

Product

Resources

About