Reservoir monitoring by a 4-D electrical technique

Ushijima, Kazuo; Mizunaga, Hideki; Tanaka, Toshiaki

doi:10.1190/1.1438242

Cited by 30 publications

(23 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ramirez et al (1996) monitor tracer movements using a tank and boreholes as electrodes. An application with a geothermal background is performed by Ushijima et al (1999), in which fluid flow is monitored. In the context of CO 2 injection, Ramirez et al (2003) conduct sensitivity studies comparing LE surveys with vertical point electrode surveys.…”

Section: Introductionmentioning

confidence: 99%

Numerical study of long-electrode electric resistivity tomography — Accuracy, sensitivity, and resolution

2015

View full text Add to dashboard Cite

Electric resistivity tomography (ERT) is a widespread technique used for geologic and hydrological subsurface characterization. The 3D application is limited to small scales due to the enormous effort required for field surveys. Long-electrode (LE)-ERT using steel-cased boreholes can overcome small-scale limitations and has recently gained significant attention. However, no systematic investigation concerning the performance of long electrodes has been performed. We have conducted synthetic studies of LE-ERT to understand its advantages and limitations. We have compared three different approaches of modeling long electrodes, placing particular emphasis on the complete electrode model, to determine which reflects the physical reality best and thus can be used as a benchmark. The conductive cell model led to comparable results but was numerically more expensive. An interesting alternative approach was the shunt electrode model, which does not require discretizing the lateral extension of the casing. Systematic sensitivity studies revealed that model resolution could be enhanced in the borehole depth range through the use of electrodes of different lengths or surface electrodes. Varying contact impedances along different sections of the borehole can change the electric field visibly and influence four-point measurements. Even if large electrode segments show reduced coupling, the influence on voltage measurements was below 4% for realistic contact impedances. We have proven the applicability of LE-ERT for imaging lateral saltwater movement through the simulation of simple scenarios in the context of saltwater intrusion. Our synthetic examples determined the advantage of long electrodes compared with simulations using surface electrodes. The 3D inversion of synthetic data sets revealed that the modeled anomalies could be imaged in most cases. Different models revealed limitations due to poor vertical resolution and supported the usage of casings with different lengths or in combination with surface electrodes to improve resolution.

show abstract

Section: Introductionmentioning

confidence: 99%

Numerical study of long-electrode electric resistivity tomography — Accuracy, sensitivity, and resolution

2015

View full text Add to dashboard Cite

show abstract

“…The "fluid-flow tomography" method has been developed by Geophysics Laboratory, Kyushu University since 1999 (Ushijima et al, 1999). The method is used to monitor the transient phenomena of dynamic fluidflow behavior during water injection and production operations of a geothermal field.…”

Section: Geological Settingsmentioning

confidence: 99%

“…4. Field survey of the "fluid-flow tomography" method (Ushijima et al, 1999). and approximation ∂φ/∂η value, the set of simultaneous equations is given as…”

Section: Mam 3-d Forward Problemmentioning

confidence: 99%

See 1 more Smart Citation

3-D inversion of borehole-to-surface electrical data using a back-propagation neural network

2009

Journal of Applied Geophysics

View full text Add to dashboard Cite

“…Stierman (1984) used the method to detect contaminated ground water near a waste disposal site. Ushijima et al (1999) achieved a favorable outcome in keeping track of forward direction of high temperature superheated steam that was available for producing heavy oil. Through numerical simulation method, Guo et al (2006) studied electrical response of layered media by surface-borehole technique.…”

Section: Introductionmentioning

confidence: 99%

Research on Heavy Oil Thermal Recovery by CO₂ Steam Flooding with Help of Combination of Borehole-Surface Electric Potential and Cross-Borehole Electric Potential

Fujimitsu

2011

Energy Exploration & Exploitation

View full text Add to dashboard Cite

With an increasing tendency towards more demand for energy resources, the supply of energy as a focus of global strategy is attracting more and more attention from the world. However, on the one hand, conventional hydrocarbon resources are decreasing gradually, and therefore it is definitely an urgent task to search for renewable and replaceable resources at the present time. On the other hand, it has been proved that the total reserves of heavy oil are already up to 1105×108 tons around the world, which means that exploring heavy oil can be a beneficial supplement for alleviating the shortage of oil and gas. Moreover, it is noteworthy that because the heavy oil can be exploited by heated CO 2 , collecting and consuming CO 2 during the production process will help to relieve global warming.In this study, we take the feasibility of heavy oil recovery by CO 2 steam into consideration only from the viewpoint of geophysics. In the process of research, with the help of borehole-surface electric potential and cross-borehole electric potential, the entire procedures from heating heavy oil reservoir and optimizing the location of well to deciding the layer of perforation are exhibited completely. In the course of calculation, potential distributions corresponding to a point source of current are acquired by solving the Poisson equation using a direct and explicit finite difference technique for a lower half-space with 3-D distribution of conductivity. As for computation of a large sparse matrix, the technique of nonzero bandwidth storage and the Incomplete Cholesky Conjugate Gradient method are adopted. The consequences prove that with the assistance of crossborehole electric potential combining with borehole-surface electric potential, the project of heavy oil recovery by CO 2 steam is feasible and effective.

show abstract

Reservoir monitoring by a 4-D electrical technique

Cited by 30 publications

References 0 publications

Numerical study of long-electrode electric resistivity tomography — Accuracy, sensitivity, and resolution

Numerical study of long-electrode electric resistivity tomography — Accuracy, sensitivity, and resolution

3-D inversion of borehole-to-surface electrical data using a back-propagation neural network

Research on Heavy Oil Thermal Recovery by CO₂ Steam Flooding with Help of Combination of Borehole-Surface Electric Potential and Cross-Borehole Electric Potential

Contact Info

Product

Resources

About

Reservoir monitoring by a 4-D electrical technique

Cited by 30 publications

References 0 publications

Numerical study of long-electrode electric resistivity tomography — Accuracy, sensitivity, and resolution

Numerical study of long-electrode electric resistivity tomography — Accuracy, sensitivity, and resolution

3-D inversion of borehole-to-surface electrical data using a back-propagation neural network

Research on Heavy Oil Thermal Recovery by CO2 Steam Flooding with Help of Combination of Borehole-Surface Electric Potential and Cross-Borehole Electric Potential

Contact Info

Product

Resources

About

Research on Heavy Oil Thermal Recovery by CO₂ Steam Flooding with Help of Combination of Borehole-Surface Electric Potential and Cross-Borehole Electric Potential