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.

scholarly journals On the Use of Electrical Resistivity Method in Mapping Potential Sources and Extent of Pollution of Groundwater Systems in Lapai Town, Niger State, Nigeria.

2021 ◽  
Vol 5 (1) ◽  
pp. 18
Author(s):  
Matthew Tersoo Tsepav ◽  
Aliyu Yahaya Badeggi ◽  
Obaje Nuhu George ◽  
Usman Yusuf Tanko ◽  
Ibrahim Samuel Ibbi
Keyword(s):  
Electrical Resistivity ◽  
Lateritic Soil ◽  
Protective Capacity ◽  
Unconfined Aquifers ◽  
Resistivity Method ◽  
Electrical Sounding ◽  
Groundwater Systems ◽  
Electrical Resistivity Method ◽  
Resistivity Meter ◽  
Confined And Unconfined Aquifers

<p>Electrical resistivity method employing the Schlumberger array was used to occupy forty four (44) vertical electrical sounding points in Lapai town with the aim of determining the depth to aquifers, aquifer thicknesses and aquifer protective capacity. The G41 Geotron resistivity meter was used in obtaining the apparent resistivity data which was processed using Interpex 1XD resistivity interpretation software. The results revealed four lithologic sections which include top lateritic soil, sandy clay, fractured basement and fresh basement. Both confined and unconfined aquifers were identified within the area, with four classes of aquifer proactive capacities as high, moderate, weak and poor. While the aquifer at VES 20 was highly protected, twenty other aquifers were moderately protected, eight others had weak protection and fifteen aquifers were poorly protected. The aquifers were generally of good thicknesses and at varying reasonable depths, making them good reservoirs of water in appreciable quantity. The average aquifer thickness was estimated to be 48.36m while the average depth to aquifers was estimated to be 56.68m.</p>

Dual attenuation peaks revealing mesoscopic and microscopic fluid flow in partially oil-saturated Fontainebleau sandstones

2020 ◽  
Vol 224 (3) ◽  
pp. 1670-1683
Author(s):  
Liming Zhao ◽  
Genyang Tang ◽  
Chao Sun ◽  
Jianguo Zhao ◽  
Shangxu Wang
Keyword(s):  
Fluid Flow ◽  
Reservoir Characterization ◽  
Seismic Analysis ◽  
Confining Pressure ◽  
Time Lapse ◽  
Seismic Attenuation ◽  
Fluid Distribution ◽  
Oil Viscosity ◽  
Measurement Results ◽  
And Shifts

SUMMARY We conducted stress–strain oscillation experiments on dry and partially oil-saturated Fontainebleau sandstone samples over the 1–2000 Hz band at different confining pressures to investigate the wave-induced fluid flow (WIFF) at mesoscopic and microscopic scales and their interaction. Three tested rock samples have similar porosity between 6 and 7 per cent and were partially saturated to different degrees with different oils. The measurement results exhibit a single or two attenuation peaks that are affected by the saturation degree, oil viscosity and confining pressure. One peak, exhibited by all samples, shifts to lower frequencies with increasing pressure, and is mainly attributed to grain contact- or microcrack-related squirt flow based on modelling of its characteristics and comparison with other experiment results for sandstones. The other peak is present at smaller frequencies and shifts to higher frequencies as the confining pressure increases, showing an opposite pressure dependence. This contrast is interpreted as the result of fluid flow patterns at different scales. We developed a dual-scale fluid flow model by incorporating the squirt flow effect into the patchy saturation model, which accounts for the interaction of WIFFs at microscopic and mesoscopic scales. This model provides a reasonable interpretation of the measurement results. Our broad-frequency-band measurements give physical evidence of WIFFs co-existing at two different scales, and combining with modelling results, it suggests that the WIFF mechanisms, related to pore microstructure and fluid distribution, interplay with each other and jointly control seismic attenuation and dispersion at reservoir conditions. These observations and modelling results are useful for quantitative seismic interpretation and reservoir characterization, specifically they have potential applications in time-lapse seismic analysis, fluid prediction and reservoir monitoring.

Analysis of landslide area of Tulung subdistrict, Ponorogo, Indonesia in 2017 using resistivity method

2020 ◽  
Vol 9 (4) ◽  
pp. 341-360
Author(s):  
Adi Susilo ◽  
Fina Fitriah ◽  
Sunaryo ◽  
Eng Turniningtyas Ayu Rachmawati ◽  
Eko Andi Suryo
Keyword(s):  
Design Methodology ◽  
Research Area ◽  
Electric Resistivity ◽  
Disaster Mitigation ◽  
Track Length ◽  
Landslide Area ◽  
Content Type ◽  
Resistivity Method ◽  
Geological Maps ◽  
Measured Resistivity

PurposeResearch has been conducted to analyze the landslide in Banaran area, Ponorogo Regency. The landslides occurred on April 1, 2017. This study was conducted to know the subsurface conditions in the Banaran area to analyze the disaster mitigation efforts. The mitigation efforts are made to reduce the risk from landslides and possible landslides.Design/methodology/approachThe method used is the geo-electric resistivity method of Wenner–Schlumberger configuration. The research was conducted in three villages namely Banaran Village, Bekirang Village and Mendak Village.FindingsThere are 12 resistivity measuring points with a track length of 410 m and a space of 10 m. The measured resistivity range is between 1.42 Ω.m and 67.500 Ω.m. The resistivity data and the local geological maps interpreted that the rocks in the Banaran area consist of clay, tuff lapilli, volcanic breccia and andesite lava. The landslide area begins at a depth of 8–35 m below the surface which is interpreted as tuff. Also, the thickness of the landslide material and the slope is = 400 which supports the occurrence of a more prominent landslide. The results of the parameter scoring of the landslide-prone areas indicated that the research area is very vulnerable to a landslide. The results of the interpretation indicate that the geo-electric resistivity method can provide a good overview for conducting landslide analysis, that is field slippage and potential material thickness occurrence landslide.Originality/valueThis article is very specific as it attempts to discover how prone Banaran are is to landslide.

scholarly journals Identifikasi Batuan Gunung Api Purba di Pegunungan Selatan Yogyakarta Bagian Barat Berdasarkan Pengukuran Geolistrik

EKSPLORIUM ◽  
2015 ◽  
Vol 36 (1) ◽  
pp. 57 ◽  
Author(s):  
Winarti Winarti ◽  
Hill Gendoet Hartono
Keyword(s):  
Volcanic Rock ◽  
Volcanic Rocks ◽  
High Resistivity ◽  
Basalt Lava ◽  
Measurement Results ◽  
Dipole Configuration

Daerah penelitian berada di perbatasan antara Dataran Yogyakarta dengan Pegunungan Selatan Yogyakarta bagian barat. Secara morfologi dan litologi yang tersingkap, indikasi gunung api purba yang dibuktikan dengan keterdapatan batuan gunung api seperti lava, breksi, dan tuf. Tujuan dari penelitian ini adalah identifikasi adanya batuan gunung api purba di bawah permuaan sepanjang Berbah-Imogiri berdasarkan data geolistrik. Metode yang digunakan adalah melakukan pengukuran geolistrik di empat lokasi secara mapping dengan konfigurasi dipole-dipole. Panjang bentangan untuk setiap lintasan 500 meter. Hasil pengukuran geolistrik menunjukkan pada lintasan 1 di Sumber Kulon-Kalitirto, Kecamatan Berbah,diinterpretasi adanya batuan gunung api berupa lava basal dan tuf. Lintasan 2 di Pilang-Srimulyo, Kecamatan Piyungan, diinterpretasi berupa breksi skoria. Lintasan 3 di Ngeblak-Bawuran, Kecamatan Pleret, diinterpretasi adanya tuf dan lava. Lintasan 4 di Guyangan-Wonolelo, Kecamatan Pleret diinterpretasi berupa tuf dan lava. Batuan gunung api secara umum terbaca mempunyai nilai tahanan jenis yang tinggi, yaitu >300 Ωm. Adanya kandungan air atau mineralisasi cenderung menurunkan nilai tahan jenis batuan gunung api tersebut. The study area is located between western part of Yogyakarta plains and Southern Mountains. The morphology and lithology along the Berbah-Imogiri show the existence of an ancient volcano. This is proven by outcrop of volcanic rock like lava, breccia and tuff. The aim of this study is to identify the existence of ancient volcanic rocks along Berbah-Imogiri based on geoelectrical data. The method used  to perform measurements at four locations geoelectrical mapping with dipole-dipole configuration a long stretch of track for every 500 meters. Geoelectrical measurement results showed on track 1 in Source Kulon-Kalitirto, District Berbah, interpretedas  volcanic rocks such as basalt lava and tuff. Tracks 2 in Pilang-Srimulyo, District Piyungan, iterpreted as volcanic rocks of scoria breccia. Tracks 3 in Ngeblak-Bawuran, District Pleret, interpreted as lava and tuff. And track 4 on Guyangan-Wonolelo, District Pleret interpreted as form of tuff and lava. Volcanic rocks are generally having a high resistivity value > 300 Ωm. The content of water or mineralization tends to reduce the resistivity value of resistant volcanic rock.

Evaluating Global Land Surface Models in CMIP5: Analysis of Ecosystem Water- and Light-Use Efficiencies and Rainfall Partitioning

2018 ◽  
Vol 31 (8) ◽  
pp. 2995-3008 ◽  
Author(s):  
Longhui Li ◽  
Yingping Wang ◽  
Vivek K. Arora ◽  
Derek Eamus ◽  
Hao Shi ◽  
...  
Keyword(s):  
Land Surface ◽  
Model Simulation ◽  
Gross Primary Production ◽  
Model Development ◽  
Coupled Model ◽  
Functional Constraints ◽  
Model Simulations ◽  
Ensemble Mean ◽  
Dry Conditions ◽  
Use Efficiency

Abstract Water and carbon fluxes simulated by 12 Earth system models (ESMs) that participated in phase 5 of the Coupled Model Intercomparison Project (CMIP5) over several recent decades were evaluated using three functional constraints that are derived from both model simulations, or four global datasets, and 736 site-year measurements. Three functional constraints are ecosystem water-use efficiency (WUE), light-use efficiency (LUE), and the partitioning of precipitation P into evapotranspiration (ET) and runoff based on the Budyko framework. Although values of these three constraints varied significantly with time scale and should be quite conservative if being averaged over multiple decades, the results showed that both WUE and LUE simulated by the ensemble mean of 12 ESMs were generally lower than the site measurements. Simulations by the ESMs were generally consistent with the broad pattern of energy-controlled ET under wet conditions and soil water-controlled ET under dry conditions, as described by the Budyko framework. However, the value of the parameter in the Budyko framework ω, obtained from fitting the Budyko curve to the ensemble model simulation (1.74), was larger than the best-fit value of ω to the observed data (1.28). Globally, the ensemble mean of multiple models, although performing better than any individual model simulations, still underestimated the observed WUE and LUE, and overestimated the ratio of ET to P, as a result of overestimation in ET and underestimation in gross primary production (GPP). The results suggest that future model development should focus on improving the algorithms of the partitioning of precipitation into ecosystem ET and runoff, and the coupling of water and carbon cycles for different land-use types.

scholarly journals Analytical and Numerical Groundwater Flow Solutions for the FEMME-Modeling Environment

Hydrology ◽  
2020 ◽  
Vol 7 (2) ◽  
pp. 27 ◽  
Author(s):  
Mustafa El-Rawy ◽  
Okke Batelaan ◽  
Kerst Buis ◽  
Christian Anibas ◽  
Getachew Mohammed ◽  
...  
Keyword(s):  
Water Level ◽  
Numerical Solutions ◽  
Groundwater Model ◽  
One Dimensional ◽  
Water Interaction ◽  
Unconfined Aquifers ◽  
Different Types ◽  
Groundwater Surface Water Interaction ◽  
Confined And Unconfined Aquifers ◽  
Good Agreement

Simple analytical and numerical solutions for confined and unconfined groundwater-surface water interaction in one and two dimensions were developed in the STRIVE package (stream river ecosystem) as part of FEMME (flexible environment for mathematically modelling the environment). Analytical and numerical solutions for interaction between one-dimensional confined and unconfined aquifers and rivers were used to study the effects of a 0.5 m sudden rise in the river water level for 24 h. Furthermore, a two-dimensional groundwater model for an unconfined aquifer was developed and coupled with a one-dimensional hydrodynamic model. This model was applied on a 1 km long reach of the Aa River, Belgium. Two different types of river water level conditions were tested. A MODFLOW model was set up for these different types of water level condition in order to compare the results with the models implemented in STRIVE. The results of the analytical solutions for confined and unconfined aquifers were in good agreement with the numerical results. The results of the two-dimensional groundwater model developed in STRIVE also showed that there is a good agreement with the MODFLOW solutions. It is concluded that the facilities of STRIVE can be used to improve the understanding of groundwater-surface water interaction and to couple the groundwater module with other modules developed for STRIVE. With these new models STRIVE proves to be a powerful example as a development and testing environment for integrated water modeling.

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.

Not All Aquifers Are Created Equal

High and Dry ◽  
2017 ◽  
Author(s):  
William M. Alley ◽  
Rosemarie Alley
Keyword(s):  
Saltwater Intrusion ◽  
Sub Saharan Africa ◽  
Edwards Aquifer ◽  
Artesian Basin ◽  
Unconfined Aquifers ◽  
Rock Types ◽  
Sub Saharan ◽  
Artesian Wells ◽  
Confined And Unconfined Aquifers ◽  
Full Consideration

This chapter examines how geology and climate create vastly different groundwater situations. Effective management of groundwater depends upon full consideration of these differences. The chapter begins with a distinction between confined and unconfined aquifers and a look at artesian wells, with a focus on Australia’s Great Artesian Basin. The characteristics of different rock types are illustrated by four basic aquifer rock types in sub-Saharan Africa. The chapter then turns to non-renewable aquifers in North Africa and Saudi Arabia. The fast-recharging Edwards Aquifer in Texas then provides a quite different story with its sensitivity to short-term climate variability and concerns about endangered species. The chapter concludes with a discussion of saltwater intrusion in coastal aquifers and the potential of brackish groundwater for water supply.

Sign in / Sign up

Export Citation Format

Share Document