scholarly journals AQUIFER DETECTION USING 2-D RESISTIVITY METHOD AND POROSITY CALCULATION

2018 ◽  
Vol 80 (6) ◽  
Author(s):  
Umi Maslinda Anuar ◽  
M. M. Nordiana
Keyword(s):  
Porous Materials ◽  
Saturated Zone ◽  
Porous Rocks ◽  
Archie’S Law ◽  
Resistivity Method ◽  
Resistivity Survey ◽  
Sedimentary Aquifer ◽  
Porosity Percentage

2-D resistivity method has been widely used for aquifer detection, where aquifers are usually made of porous rocks. The aim of this study is to detect the aquifer using 2-D resistivity method and porosity calculation from Archie’s Law. The porosity of the subsurface materials can be known and the porous materials can be easily detected. This study was done at two different locations which are in Selangor and Kelantan. Two lines of 2-D resistivity survey were conducted at each location. The results were correlated with borehole records. Only one borehole was executed at each location near to the 2-D resistivity lines. The saturated zones (1-100 Ωm) that found from the 2-D resistivity results were suspected to be an aquifer, and the zones were validated by the borehole records. Lastly, the porosity was calculated for all 2-D resistivity lines and an imaging was created for each line. A productive sedimentary aquifer should have porosity percentage of >20% and the saturated zone at both study area have porosity percentage of >20% as expected.

Exploration for Marble Deposit in Parts of Okpella, South-Southern Nigeria

2019 ◽  
pp. 1-7
Author(s):  
K. O. Ozegin
Keyword(s):  
Electrical Resistivity ◽  
Electrode Spacing ◽  
Clayey Sand ◽  
Current Electrode ◽  
Electrical Resistivity Survey ◽  
Resistivity Method ◽  
Resistivity Survey ◽  
Surface Measurements ◽  
Electrical Sounding ◽  
Electrical Resistivity Method

The ultimate aim of the electrical resistivity survey is to determine the resistivity distribution with depth on the basis of surface measurements of the apparent resistivity and to interpret it in terms of geology. Marble deposit was investigated with the application of electrical resistivity method using Vertical Electrical Sounding (VES) technique with the aim of characterising this deposit in parts of Okpella. Six (6) VES were acquired using the Schlumberger array for data acquisition with current electrode spacing varying from 1.0 to 150.0 m. The VES data obtained were interpreted using ipi2win Software. The results showed three layers indicating subsurface geologic sequence probed 26.4 m and beyond with clay/clayey sand (23.3 – 219.1 Ωm), sand (423 - 2040 Ωm) and marble (12661 - 404498 Ωm). The occurrence of marble deposit was revealed at VES points at 1, 2 and 5 in the studied area.  This study concluded that the study area had occurrence of the marble deposits, which would be of economic importance, if exploited.

Electrical-resistivity characterization of an industrial site using long electrodes

Geophysics ◽  
2010 ◽  
Vol 75 (4) ◽  
pp. WA95-WA104 ◽  
Author(s):  
Dale F. Rucker ◽  
Meng H. Loke ◽  
Marc T. Levitt ◽  
Gillian E. Noonan
Keyword(s):  
Electrical Resistivity ◽  
Liquid Waste ◽  
Near Surface ◽  
Low Resistivity ◽  
Electrical Resistivity Survey ◽  
Resistivity Method ◽  
Tank Farm ◽  
Resistivity Survey ◽  
New Strategy ◽  
Linear Conductor

An electrical-resistivity survey was completed at the T tank farm at the Hanford nuclear site in Washington State, U.S.A. The purpose of the survey was to define the lateral extent of waste plumes in the vadose zone in and around the tank farm. The T tank farm consists of single-shell tanks that historically have leaked and many liquid-waste-disposal facilities that provide a good target for resistivity mapping. Given that the site is highly industrialized with near-surface metallic infrastructure that potentially could mask any interpretable waste plume, it was necessary to use the many wells around the site as long electrodes. To accommodate the long electrodes and to simulate the effects of a linear conductor, the resistivity inversion code was modified to assign low-resistivity values to the well’s location. The forward model within the resistivity code was benchmarked for accuracy against an analytic solution, and the inverse model was tested for its ability to recreate images of a hypothetical target. The results of the tank-farm field survey showed large, low-resistivity targets beneath the disposal areas that coincided with the conceptual hydrogeologic models developed regarding the releases. Additionally, in areas of minimal infrastructure, the long-electrode method matched the lateral footprint of a 3D surface-resistivity survey with reasonable fidelity. Based on these results, the long-electrode resistivity method may provide a new strategy for environmental characterization at highly industrialized sites, provided a sufficient number and density of wells exist.

scholarly journals Simulation of Time-Lapse Resistivity Method on Sandbox Model to Determine Fluid Changes and Desaturation

2020 ◽  
Vol 5 (4) ◽  
pp. 227-233
Author(s):  
Rizka Rizka ◽  
Beta Arroma Piskora ◽  
Soni Satiawan ◽  
Hendra Saputra
Keyword(s):  
Model Simulation ◽  
Time Lapse ◽  
Track Length ◽  
Archie’S Law ◽  
Unconfined Aquifers ◽  
Resistivity Method ◽  
Measurement Results ◽  
Dry Conditions ◽  
Dipole Configuration ◽  
Confined And Unconfined Aquifers

Time-lapse resistivity method is an implementation of the resistivity method that is executed exactly at the same spot but with various in time. In this study, the technique uses to identify the dynamics of groundwater fluids. The application of the time-lapse resistivity method was carried out by performing a sandbox model simulation that contains layers of rocks with a fault structure. The rock layers consist of tuff, fine sandstone, shale, coarse sandstone, gravel that represents confined and unconfined aquifers. The simulation was achieved by applying the Electrical Resistivity Tomography (ERT) dipole-dipole configuration at the same place, and measurements with 3 different conditions, namely dry, wet conditions filled with 2.5% water and wet conditions filled with 5% water. Data acquisition uses Naniura resistivity meters with a track length of 96 cm. The first measurement results (dry conditions) obtained a range of resistivity values ​​from 3.7 to 168.1 Ω.m, the second measurement (wet conditions filled 2.5% water) obtained the range of resistivity values ​​from 3.3 to 110.8 Ω.m and the third measurement (wet conditions) filled with 5% water the resistivity values ​​range from 1.7 to 91.2 Ω.m. Following the results of time-lapse inversion processing, a larger percentage change in the amount of 5.6% due to water absorption by the surface which then migrates into the inner layer. Whereas the percentage of desaturation ranges is from -3.11 to 0.217 %, refer to Archie’s Law assumes conduction is caused by water content.

Combined application of dc and TEM to sea‐water intrusion mapping

Geophysics ◽  
1999 ◽  
Vol 64 (2) ◽  
pp. 417-425 ◽  
Author(s):  
Chieh-Hou Yang ◽  
Lun-Tao Tong ◽  
Ching-Feng Huang
Keyword(s):  
Pore Water ◽  
Sea Water ◽  
Salt Water ◽  
Joint Inversion ◽  
Empirical Relation ◽  
Dc Resistivity ◽  
Water Conductivity ◽  
Archie’S Law ◽  
Resistivity Method ◽  
Transient Electromagnetic

A geoelectric survey using a dc resistivity method and a transient electromagnetic induction (TEM) method was carried out from 1986 to 1988. It was used to help map the lateral and vertical distributions of the freshwater/salt‐water interface in the Pei‐kang area on the west coast of Taiwan. The dc and TEM soundings were performed at 79 localities over an area of 240 km2 of Quaternary alluvium. Significant changes in pore‐water conductivity at some places were detected by these two methods. A low resistivity value (<1.5 ohm-m) implies salt‐water contamination of groundwater. The results of spatial distribution of apparent resistivity indicate the salt‐water‐affected aquifers are confined to the southwest part of the study area, and the affected aquifers are confined to the top of two aquifers. A geoelectric model with three to four layers is inferred from the joint inversion of dc and TEM data. Based on a modified Archie’s law suggested by the authors, an empirical relation between pore‐water resistivity of the stratum and formation resistivity can be obtained. It can be used to convert the computed resistivity of each geoelectric layer (aquifer) to the resistivity of the water contained in these layer, thus leading to the assessment of groundwater contamination. Repeated dc resistivity measurements have been carried out at selected locations once every year from 1986 to 1988. These data were used to monitor the temporal variation and a possible spreading of the salt‐water invasion. During 1995, a dc survey was conducted in the same area to compare with the dc sounding results obtained in 1988. The final results provide an evaluation of the efficiency of groundwater management in the study area.

Archie's law from a fractal model for porous rocks

1997 ◽  
Vol 55 (13) ◽  
pp. 8038-8041 ◽  
Author(s):  
Shashwati Roy ◽  
S. Tarafdar
Keyword(s):  
Fractal Model ◽  
Porous Rocks ◽  
Archie’S Law

A quadripole resistivity survey of the Imperial Valley, California

Geophysics ◽  
1978 ◽  
Vol 43 (7) ◽  
pp. 1485-1500 ◽  
Author(s):  
Norman Harthill
Keyword(s):  
Electric Fields ◽  
Geothermal Field ◽  
Imperial Valley ◽  
Produce Water ◽  
The North ◽  
Resistivity Method ◽  
Resistivity Survey ◽  
Geothermal Fields ◽  
Measurement Location ◽  
The City

A quadripole resistivity survey of the Imperial Valley, California was carried out from the Salton Sea in the north to the Mexican border in the south. The east and west boundaries of the survey were the topographic limits of the valley. The quadripole resistivity method consists of sequentially energizing two orthogonal bipole sources with a square wave of electric current and measuring the resultant electric fields with a pair of orthogonal wire receivers. Two resultant electric fields are measured and by combining them in different proportions, their resultant can be made to rotate through 360 degrees. By performing this procedure, an ellipse of resistivity can be calculated at each measurement location. The arithmetic mean of the maximum and minimum axes of the ellipse is a tensor invariant resistivity. It was this value which was used to define the variation of electrical resistivity over the Imperial Valley. The quadripole survey of the Imperial Valley was undertaken to compare its known geothermal fields with previously unsurveyed areas. The results show that the geothermal fields of the Imperial Valley have distinctive resistivity characteristics. A large circular area south of the city of Brawley was found which has the same characteristics as the known geothermal fields. From the resistivity data, it is predicted that this south Brawley resistivity anomaly represents a geothermal field which will produce water with a temperature of approximately 200°C and with a salinity between 20,000 and 50,000 ppm. A well to test the prospect was scheduled to be drilled early in 1978.

Potential soil characteristics for riverbank filtration using 2-D ground resistivity in Kota Lama Kiri, Kuala Kangsar

2016 ◽  
Vol 16 (6) ◽  
pp. 1477-1483 ◽  
Author(s):  
Mohd Firdaus Abdul Razak ◽  
Md Azlin Md Said ◽  
Rais Yusoh ◽  
Rosmyra Jasmi
Keyword(s):  
Riverbank Filtration ◽  
Electrode Spacing ◽  
High Permeability ◽  
Resistivity Method ◽  
Data Process ◽  
Resistivity Survey ◽  
Sand And Gravel ◽  
Suitable Area ◽  
Subsurface Resistivity ◽  
Aquifer Type

Identifying the subsurface profile for riverbank/bed filtration (RBF) using conventional methods such as drilled boreholes is usually labor intensive, costly and acquires only 1-D profiling. Hence, a 2-D ground resistivity method was used as an alternative to obtain a 2-D subsurface profile by extending to 200 m length at Kota Lama Kiri, Kuala Kangsar, Perak site area. Four resistivity survey lines (200 m each) with minimum electrode spacing of 5 m were executed at the site area. The Wenner-Schlumberger array protocol was applied for acquisition data process. The resistivity data were then processed and interpreted using RES2DINV software. The results show the approximate 2-D pseudo-section image of the subsurface resistivity distribution with different soil types. The interpretation of results reveals that the site area consists of two main layers: (a) sand and gravel (300–750 Ωm) from 0 to 10 m depth, and (b) weathered rock (0–350 Ωm) within 10 to 40 m depth. It found that the first layer (0–10 m depth) belongs to the alluvial aquifer type and has a relatively high permeability, thus suitable for RBF. This method is believed to be able to give great assistance for selecting the suitable area for RBF in the future.

Sign in / Sign up

Export Citation Format

Share Document