Using surface deformation to image reservoir dynamics

The inversion of surface deformation data such as tilt, displacement, or strain provides a noninvasive method for monitoring subsurface volume change. Reservoir volume change is related directly to processes such as pressure variations induced by injection and withdrawal. The inversion procedure is illustrated by an application to tiltmeter data from the Hijiori test site in Japan. An inversion of surface tilt data allows us to image flow processes in a fractured granodiorite. Approximately 650 barrels of water, injected 2 km below the surface, produces a peak surface tilt of the order of 0.8 microradians. We find that the pattern of volume change in the granodiorite is very asymmetrical, elongated in a north‐northwesterly direction, and the maximum volume change is offset by more than 0.7 km to the east of the pumping well. The inversion of a suite of leveling data from the Wilmington oil field in Long Beach, California, images large‐scale reservoir volume changes in 12 one‐ to two‐year increments from 1976 to 1996. The influence of various production strategies is seen in the reservoir volume changes. In particular, a steam flood in fault block II in the northwest portion of the field produced a sudden decrease in reservoir volume.

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Reservoir-Induced Land Deformation: Case Study from the Grand Ethiopian Renaissance Dam

Remote Sensing ◽

10.3390/rs13050874 ◽

2021 ◽

Vol 13 (5) ◽

pp. 874

Author(s):

Yu Chen ◽

Mohamed Ahmed ◽

Natthachet Tangdamrongsub ◽

Dorina Murgulet

Keyword(s):

Land Surface ◽

Large Scale ◽

Surface Deformation ◽

Vertical Displacement ◽

Nile River ◽

Reservoir Volume ◽

Novel Approach ◽

Land Deformation ◽

Large Scale Land ◽

The Impact

The Nile River stretches from south to north throughout the Nile River Basin (NRB) in Northeast Africa. Ethiopia, where the Blue Nile originates, has begun the construction of the Grand Ethiopian Renaissance Dam (GERD), which will be used to generate electricity. However, the impact of the GERD on land deformation caused by significant water relocation has not been rigorously considered in the scientific research. In this study, we develop a novel approach for predicting large-scale land deformation induced by the construction of the GERD reservoir. We also investigate the limitations of using the Gravity Recovery and Climate Experiment Follow On (GRACE-FO) mission to detect GERD-induced land deformation. We simulated three land deformation scenarios related to filling the expected reservoir volume, 70 km3, using 5-, 10-, and 15-year filling scenarios. The results indicated: (i) trends in downward vertical displacement estimated at −17.79 ± 0.02, −8.90 ± 0.09, and −5.94 ± 0.05 mm/year, for the 5-, 10-, and 15-year filling scenarios, respectively; (ii) the western (eastern) parts of the GERD reservoir are estimated to move toward the reservoir’s center by +0.98 ± 0.01 (−0.98 ± 0.01), +0.48 ± 0.00 (−0.48 ± 0.00), and +0.33 ± 0.00 (−0.33 ± 0.00) mm/year, under the 5-, 10- and 15-year filling strategies, respectively; (iii) the northern part of the GERD reservoir is moving southward by +1.28 ± 0.02, +0.64 ± 0.01, and +0.43 ± 0.00 mm/year, while the southern part is moving northward by −3.75 ± 0.04, −1.87 ± 0.02, and −1.25 ± 0.01 mm/year, during the three examined scenarios, respectively; and (iv) the GRACE-FO mission can only detect 15% of the large-scale land deformation produced by the GERD reservoir. Methods and results demonstrated in this study provide insights into possible impacts of reservoir impoundment on land surface deformation, which can be adopted into the GERD project or similar future dam construction plans.

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Constraints on the location, depth and yield of the 2017 September 3 North Korean nuclear test from InSAR measurements and modelling

Geophysical Journal International ◽

10.1093/gji/ggz451 ◽

2019 ◽

Vol 220 (1) ◽

pp. 345-351 ◽

Cited By ~ 3

Author(s):

K M Sreejith ◽

Ritesh Agrawal ◽

A S Rajawat

Keyword(s):

Large Scale ◽

Surface Deformation ◽

Nuclear Explosion ◽

Source Parameters ◽

Test Site ◽

Nuclear Test ◽

Interferometric Synthetic Aperture Radar ◽

Surface Displacements ◽

Detailed Surface ◽

Scale Surface

SUMMARY The Democratic People's Republic of Korea (North Korea) conducted its sixth and largest affirmed underground nuclear test on 2017 September 3. Analysis of Interferometric Synthetic Aperture Radar (InSAR) data revealed detailed surface displacements associated with the nuclear explosion. The nuclear explosion produced large-scale surface deformation causing decorrelation of the InSAR data directly above the test site, Mt. Mantap, while the flanks of the Mountain experienced displacements up to 0.5 m along the Line-of-Sight of the Satellite. We determined source parameters of the explosion using the Bayesian inversion of the InSAR data. The explosive yield was estimated as 245–271 kiloton (kt) of TNT, while the previous yield estimations range from 70–400 kt. We determined the nuclear source at a depth of 542 ± 30 m below Mt. Mantap (129.0769°E, 41.0324°N). We demonstrated that the Bayesian modelling of the InSAR data reduces the uncertainties in the source parameters of the nuclear test, particularly the yield and source depth that are otherwise poorly resolved in seismic methods.

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An extracorporeal reservoir device for continuous monitoring of tissue volume change

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1982.242.4.h698 ◽

1982 ◽

Vol 242 (4) ◽

pp. H698-H704

Author(s):

H. I. Chen

Keyword(s):

Volume Change ◽

Continuous Monitoring ◽

Venous Pressure ◽

Indirect Measurement ◽

Constant Flow ◽

Volume Changes ◽

Arterial Perfusion ◽

Tissue Volume ◽

Reservoir Volume ◽

Tissue Handling

The conventional use of a gravimetric or plethysmographic method for continuous monitoring of tissue volume changes has some inherent problems related to organ exteriorization, denervation, and tissue handling. A new method using an extracorporeal reservoir is devised for indirect measurement of tissue volume changes. When the organ is perfused with constant flow and the venous outflow is collected in a reservoir, the reservoir volume reaches a steady level by pumping out equal amount of blood entering the reservoir. Under this condition, every perturbation causing a change in tissue volume will result in a reservoir volume change of the opposite direction. Two different pressure-regulating systems are also designed for the control of arterial perfusion pressure. Because volume change is not allowed to occur inside the regulating system, the device still guarantees that the reverse change in reservoir volume reflects the tissue volume change on alteration of arterial perfusion from constant-flow to constant-pressure condition. The method has been tested in six canine ileum segments by comparing the reservoir volume with the tissue volume recorded with direct gravimetric measurement. Experimental trials include venous pressure elevation, arterial perfusion changes, and intra-arterial infusion of vasoactive agents. The tests indicate that the tissue volume changes can be faithfully measured from the reverse change in reservoir volume. The technical advantages and possible applications of the reservoir method in the realm of hemodynamic and microcirculatory studies are also discussed.

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Mapping Reservoir Volume Changes During Cyclic Steam Stimulation Using Tiltmeter Based Surface Deformation Measurements

10.2118/97848-ms ◽

2005 ◽

Cited By ~ 6

Author(s):

Jing Du ◽

Simon John Brissenden ◽

Peter McGillivray ◽

Stephen James Bourne ◽

Paul Hofstra ◽

...

Keyword(s):

Surface Deformation ◽

Volume Changes ◽

Reservoir Volume ◽

Cyclic Steam Stimulation ◽

Deformation Measurements ◽

Steam Stimulation

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On the use of quasi-static deformation to understand reservoir fluid flow

Geophysics ◽

10.1190/1.1993711 ◽

2005 ◽

Vol 70 (4) ◽

pp. O13-O27 ◽

Cited By ~ 25

Author(s):

Don W. Vasco ◽

Alessandro Ferretti

Keyword(s):

Fluid Flow ◽

Surface Deformation ◽

Equations Of Motion ◽

Time Lapse ◽

Oil Field ◽

Static Deformation ◽

Flow Properties ◽

Reservoir Volume ◽

Reservoir Permeability ◽

Surface Displacements

Deformation above a producing reservoir provides a valuable source of information concerning fluid flow and flow properties. Quasi-static deformation occurs when the displacements are so slow that we may neglect inertial terms in the equations of motion. We present a method for inferring reservoir volume change and flow properties, such as permeability, from observations of quasi-static deformation. Such displacements may represent surface deformation such as tilt, leveling, interferometric synthetic aperture radar (InSAR), or bathymetry observations or subsurface deformation, as inferred from time-lapse seismic surveys. In our approach, the equation for fluid flow in a deforming reservoir provides a mapping from estimated fractional volume changes to reservoir permeability variations. If the reservoir behaves poroelastically over the interval of interest, all the steps in this approach are linear. Thus, the inference of reservoir permeability from deformation data becomes a linear inverse problem. In an application to the Wilmington oil field in California, we find that observed surface displacements, obtained by leveling and InSAR, are indeed compatible with measured reservoir volume fluxes. We find that the permeability variations in certain layers coincide with fault-block boundaries suggesting that, in some cases, faults are controlling fluid flow at depth.

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