Читать книгу Geophysical Monitoring for Geologic Carbon Storage - Группа авторов - Страница 4

1 Chapter 2Figure 2.1 A schematic showing the relationship between ground displacement ...Figure 2.2 Example of motion decomposition combining ascending and descendin...Figure 2.3 Range changes above the carbon storage site at In Salah, Algeria,...Figure 2.4 (a) Onset time of the most rapid change in reservoir volume. The ...Figure 2.5 (a) Detailed view of range change above well KB‐502 following 1,0...Figure 2.6 (a) Vertical displacements above well KB‐501, derived from X‐band...Figure 2.7 Distribution of total aperture change (effective fracture zone op...Figure 2.8 Calculated vertical displacement based upon the distribution of a...Figure 2.9 (a) Location of the Aquistore storage site in Saskatchewan, Canad...Figure 2.10 (a) RADARSAT‐2 Spotlight 12 SAR intensity image acquired on 23 A...Figure 2.11 Observed (a) vertical and (b) east‐west horizontal deformation r...Figure 2.12 Two components of displacement associated with point P2 from Fig...Figure 2.13 (a) Distribution of scatterers in the region surrounding the inj...Figure 2.14 Average range change from the 21 artificial reflectors installed...Figure 2.15 Time series of two measurement points in the vicinity of the inj...

2 Chapter 3Figure 3.1 The CO₂ produced from several anthropogenic and natural processes...Figure 3.2 A FMS instrument produces sidebands (ω_c ± ω_m) shifted from the ca...Figure 3.3 The in situ FMS instrument built at Los Alamos National Laborator...Figure 3.4 An example of (a) Voigt absorption profile and (b) the correspond...Figure 3.5 (a) A relatively sharp Voigt absorption profile and (b) the corre...Figure 3.6 Least‐squares fitting of FMS spectra. “Simulated” FMS data (the b...Figure 3.7 The derivative shaped FMS spectrum recorded for several (a) ¹²C¹⁶ Figure 3.8 A demonstration of the FMS accuracy and sensitivity where calibra...Figure 3.9 A comparison of the FMS stable isotope concentrations measured in...Figure 3.10 The remote FMS instrument was deployed to the ZERT controlled‐re...

3 Chapter 4Figure 4.1 The procedure for optimal design of seismic network for microseis...Figure 4.2 The location of the Kimberlina CCUS (carbon capture, utilization,...Figure 4.3 P‐wave velocity model for the Kimberlina site.Figure 4.4 The true locations of microseismic events (black dots) used in th...Figure 4.5 The initial (blue dots) and relocated (red dots) microseismic eve...Figure 4.6 The initial (blue dots) and relocated (red dots) microseismic eve...Figure 4.7 Event location accuracy versus the total number of seismic statio...Figure 4.8 (a,b) Two examples of the irregularly distributed 25 seismic stat...Figure 4.9 Comparison between mean event location accuracy for regularly spa...Figure 4.10 The true locations of microseismic events (black dots) used for ...Figure 4.11 The initial (blue dots) and relocated (red dots) microseismic ev...Figure 4.12 Event location accuracy versus the total number of geophones for...

4 Chapter 5Figure 5.1 Split‐Hopkinson Resonant Bar. A small (typically 2.5 cm–10 cm lon...Figure 5.2 Photograph of an on‐going scCO₂ injection experiment. The experim...Figure 5.3 Examples of experimentally measured frequency response functions ...Figure 5.4 Young's modulus E and shear modulus G and their attenuations dete...Figure 5.5 Young's modulus and related attenuations determined from SHRB tes...Figure 5.6 Shear modulus and related attenuations determined from SHRB tests...Figure 5.7 X‐ray CT images of scCO₂ invasion into intact and fractured sands...Figure 5.8 Fluid substitution modeling of the impact of fracture compliance ...Figure 5.9 Young's modulus E and its related attenuation a_E compared with th...Figure 5.10 Comparison between the scCO₂ saturations in Frac IIb sample with...Figure 5.11 Changes in the uniaxial Skempton coefficients B/3 and B^F/3 durin...

5 Chapter 6Figure 6.1 (a) Ultrasonic waveform recorded passing through the aluminum ref...Figure 6.2 (a) Project work‐flow diagram highlighting the rock physics exper...Figure 6.3 (a) V_p‐V_s relationship for all rhyolite core data; (b) temperatur...Figure 6.4 (a) V_p vs effective pressure for various temperature experiments ...Figure 6.5 (a) V_p vs effective pressure for various temperature experiments ...Figure 6.6 (a) Q_p vs effective pressure for the low porosity rhyolite core; ...Figure 6.7 (a) Q_p vs effective pressure for the high porosity rhyolite core;...Figure 6.8 (a) λ_ρ vs μ_ρ moduli and (b) Young's modulus versus Pois...Figure 6.9 (a) and (c) Interpretation Young's modulus vs Poisson's ratio, an...Figure 6.10 Fluid saturation P‐wave velocity measurements for the (a) low po...Figure 6.11 (a) V_P‐V_S1 data for the fluid saturation experiments for both th...Figure 6.12 Attenuation results for the fluid substitution experiments for t...Figure 6.13 Fourth generation medical imaging resolution CT scan of low poro...Figure 6.14 λ_ρ‐μ_ρ data for all fluid saturation experiments for bo...Figure 6.15 Poisson's ratio–Young's modulus and λ_ρ‐μ_ρ data for the...

6 Chapter 7Figure 7.1 Illustrations of (a) incident elastic waves, (b) elastic‐wave ref...Figure 7.2 A 2D slice of the elastic SEG‐EAGE salt model: (a) P‐wave velocit...Figure 7.3 Distributions of elastic‐wave energies (E ^P and E ^S ), and elast...Figure 7.4 Normalized elastic‐wave energies and elastic‐wave sensitivity ene...Figure 7.5 Distributions of elastic‐wave energies (E ^P and E ^S ), and elast...Figure 7.6 Normalized elastic‐wave energies and elastic‐wave sensitivity ene...Figure 7.7 The 2D layered elastic models with a fault zone. The width of the...Figure 7.8 Spatial distribution of P‐wave sensitivity energy for the normal ...Figure 7.9 Spatial distribution of S‐wave sensitivity energy for the normal ...Figure 7.10 Normalized (a) P‐wave sensitivity energy and (b) S‐wave sensitiv...Figure 7.11 Spatial distribution of P‐wave sensitivity energy with respect t...Figure 7.12 Spatial distribution of S‐wave sensitivity energy for the revers...Figure 7.13 Normalized (a) P‐wave sensitivity energy and (b) S‐wave sensitiv...Figure 7.14 Spatial distribution of P‐wave sensitivity energy for the normal...Figure 7.15 Spatial distribution of S‐wave sensitivity energy for the normal...Figure 7.16 Normalized elastic‐wave sensitivity energies at the surface for ...Figure 7.17 Spatial distribution of P‐wave sensitivity energy for the revers...Figure 7.18 Spatial distribution of S‐wave sensitivity energy for the revers...Figure 7.19 Normalized elastic‐wave sensitivity energies at the surface for ...Figure 7.20 The modified Hess anisotropic model: Panels (a)–(d) show the ela...Figure 7.21 Wavefield snapshots of the x₃‐component of the elastic displacem...Figure 7.22 Spatial distributions of qP‐wave (a, b, c, d) and qS‐wave (e, f,...Figure 7.23 Spatial distributions of qP‐wave (a, b, c, d) and qS‐wave (e, f,...Figure 7.24 The normalized qP‐wave sensitivity energies with respect to the ...Figure 7.25 The qP‐wave (a, b) and qS‐wave (c, d) sensitivity energies with ...

7 Chapter 8Figure 8.1 A picture taken when the monitoring geophone string was cemented ...Figure 8.2 Illustration of the locations of the monitoring well, injection w...Figure 8.3 CO₂ was injected into the reservoir through three horizontal well...Figure 8.4 Typical CO₂ and water injection rates in well C313.Figure 8.5 A velocity model in blue constructed from a well log in yellow fr...Figure 8.6 (a) First‐arrival times of downgoing waves of synthetic offset VS...Figure 8.7 Velocity differences between inverted and initial velocity models...Figure 8.8 Double‐difference tomography results of source locations of basel...Figure 8.9 Double‐difference tomography results of the velocity difference p...Figure 8.10 Comparison among (a) the upgoing waves of the baseline (2007) VS...Figure 8.11 Comparison of the migration image differences obtained from (a) ...Figure 8.12 A wave‐equation migration image of the upgoing waves of the 2009...Figure 8.13 The image profiles along the monitoring well and the offset VSP ...Figure 8.14 The profiles imaging on the angle domain along the monitoring we...Figure 8.15 Illustration of the profiles along different offset VSP source l...

8 Chapter 9Figure 9.1 A map showing the location of the NS walkaway VSP shot line (blue...Figure 9.2 Flowchart of the VSP data‐processing steps.Figure 9.3 Schematic illustration of upgoing/reflection raypaths (purple lin...Figure 9.4 Common‐receiver gathers of walkaway VSP data recorded at geophone...Figure 9.5 Common‐receiver gathers of walkaway VSP data recorded at geophone...Figure 9.6 Common‐receiver gathers of walkaway VSP data recorded at geophone...Figure 9.7 RTM imaging results of (a) 2008 and (b) balanced 2009 walkaway VS...Figure 9.8 Angle‐domain RTM images: (a) before and (b) after removing artifa...Figure 9.9 The same as Figure 9.7, but with angle‐domain analysis and proces...

9 Chapter 10Figure 10.1 A velocity model obtained after applying a median filter with a ...Figure 10.2 A velocity model obtained after applying another median filter w...Figure 10.3 Conventional reverse‐time migration image of the synthetic walka...Figure 10.4 Least‐squares reverse‐time migration image of the synthetic walk...Figure 10.5 Conventional reverse‐time migration image of the synthetic walka...Figure 10.6 Least‐squares reverse‐time migration image of the synthetic walk...Figure 10.7 Shown here are 21 sources picked around a north‐south line for r...Figure 10.8 Shown here are 46 sources picked around a north‐south line for r...Figure 10.9 Image obtained using the conventional reverse‐time migration wit...Figure 10.10 Image obtained using the least‐squares reverse‐time migration w...Figure 10.11 Image obtained using the conventional reverse‐time migration wi...Figure 10.12 Image obtained using the least‐squares reverse‐time migration w...Figure 10.13 Shown here are 22 sources picked around an east‐west line for r...Figure 10.14 Shown here are 41 sources picked around an east‐west line for r...Figure 10.15 Image obtained using the conventional reverse‐time migration wi...Figure 10.16 Image obtained using the least‐squares reverse‐time migration w...Figure 10.17 Image obtained using the conventional reverse‐time migration wi...Figure 10.18 Image obtained using the least‐squares reverse‐time migration w...Figure 10.19 Source locations in a 4 km ×4 km region around the monitoring w...Figure 10.20 Front view of the 3D migration image obtained using the convent...Figure 10.21 Front view of the 3D migration image obtained using the least‐s...Figure 10.22 Back view of the 3D migration image obtained using the conventi...Figure 10.23 Back view of the 3D migration image obtained using the least‐sq...

10 Chapter 11Figure 11.1 Time‐lapse P‐wave and S‐wave velocity models for monitoring Brad...Figure 11.2 (a) Time‐lapse change in P‐wave velocity; (b) time‐lapse change ...Figure 11.3 Initial (a) P‐wave and (b) S‐wave velocity models for inversion ...Figure 11.4 Time‐lapse changes of P‐wave and S‐wave velocities in the monito...Figure 11.5 Time‐lapse changes of P‐wave and S‐wave velocities in the monito...Figure 11.6 Convergence plots of (a) the data misfit and (b) the model misfi...Figure 11.7 (a) Time‐lapse walkaway VSP surveys at the SACROC CO₂‐EOR field;...Figure 11.8 (a) Time‐lapse difference obtained using conventional waveform i...

11 Chapter 12Figure 12.1 Arbitrary seismic line through (a) Ip and (b) Is volumes includi...Figure 12.2 Stack of fractional change in shear‐wave splitting parameter in ...Figure 12.3 Crossplot of daily produced fluid in wells within Vacuum Field 9...Figure 12.4 Map of time‐lapse change in the shear‐wave splitting parameter m...Figure 12.5 Percentage difference in maximum trough amplitude between zero‐a...Figure 12.6 Map of percentage porosity in a carbonate buildup in west‐centra...Figure 12.7 Location map and stratigraphic column of the Kevin Dome Phase II...Figure 12.8 At Wallewein 22‐1 well, inverted Ip, Is, density log from indepe...Figure 12.9 (a) Inverted Is from PP‐inversion after applying a constant glob...Figure 12.10 The oscillation‐like ringing artifacts of the inverted density ...Figure 12.11 Crossplot between density porosity and computed P‐wave impedanc...Figure 12.12 Crossplot of measured density porosity and S‐wave impedance (Is...Figure 12.13 Map of implied porosity from transforms derived from porosity‐i...Figure 12.14 Mid‐Duperow porosity derived from average density values from q...Figure 12.15 Graph of average Ip values derived from the quadri‐joint invers...

12 Chapter 13Figure 13.1 This area of investigation was part of a Detailed Area Study (DA...Figure 13.2 Synthetic seismic generation and scenario comparison workflow. T...Figure 13.3 (a) CO₂‐brine mixing models. The bulk modulus and density (green...Figure 13.4 Well log with fluid substitution results: V_p, V_S, ρ, and gathers...Figure 13.5 (a) Cranfield well CFU 31F reservoir model acoustic impedance (g...Figure 13.6 (a) Cranfield preinjection and (b) postinjection reflection mode...Figure 13.7 Reflection seismic (a) before and (b) after CO₂ injection. Ampli...Figure 13.8 Preseismic and postseismic volumes used in differencing operatio...Figure 13.9 (a) P‐wave reflectivity difference volume. Arrow indicates reser...

13 Chapter 14Figure 14.1 The principle of time‐lapse gravity monitoring. In this example,...Figure 14.2 The concept of measuring gravity in borehole and obtaining appar...Figure 14.3 The density contrast (kg/m³) between CO₂ and brine as a function...Figure 14.4 The variation of density as a function of temperature and depth....Figure 14.5 The Micro‐g Lacoste A10 portable absolute gravimeterFigure 14.6 The geologic reservoir model used in the multiphase flow simulat...Figure 14.7 Cross sections of the density difference between the start and t...Figure 14.8 The surface gravity response ((Gal) associated with the CO₂ plum...Figure 14.9 The borehole gravity anomaly associated with the CO₂ plume after...Figure 14.10 Deployment of the seafloor gravimeter (ROVDOG) at the Sleipner ...Figure 14.11 Side view of the Dover 33 Reef showing the location of the deep...Figure 14.12 Time‐lapse borehole gravity survey results at the MRCSP Michiga...

14 Chapter 15Figure 15.1 Schematic sketch of a typical geological setting for CO₂ injecti...Figure 15.2 CO₂ phase diagram.Figure 15.3 Fluid resistivity as a function of NaCl concentration and temper...Figure 15.4 Rock bulk resistivity (ρ_b) as a function of CO₂ saturation (SCO₂ Sketch 15.1 Sketch 15.2 Figure 15.5 Example of an electrode array for a surface electrical survey. A...Figure 15.6 Surface bipole source and thin resistive layer model.Figure 15.7 Schlumberger response of deep conductive and resistive layers.Figure 15.8 Example of an anomaly created by a spherical cave of infinite re...Figure 15.9 (a) Change in electrical resistivity due to (b) CO₂ plume recove...Figure 15.10 (a) Schlumberger apparent resistivity response for a layer 50 m...Figure 15.11 Dipole‐dipole response for deep conductive and resistive bodies...Figure 15.12 MT response for deep conductive and resistive bodies.Figure 15.13 Spherical body in a uniform inducing field. P is the observatio...Figure 15.14 Geologic section with an irregular surface and overburden and s...Figure 15.15 Anomalous horizontal field at the surface for a resistive spher...Figure 15.16 Anomalous signal normalized by the primary field for a resistiv...Figure 15.17 B_Y (in Teslas) as a function of the depth of a 50 m resistive s...Figure 15.18 Response of a 100 Ohm‐m layer 50 m thick at a depth of 1.0 km b...Figure 15.19 The time domain response of a 50 m thick layer of 100 Ohm‐m in ...Figure 15.20 Electric field on the surface for a pole source on the surface ...

15 Chapter 16Figure 16.1 A 2D cross‐well ERT layout. Electrodes are mounted on the outsid...Figure 16.2 (a) Layout of one injection well F1 and two monitoring wells F2 ...Figure 16.3 Contact resistance showing electrode conditions: (a) normal, (b)...Figure 16.4 Top row: Time‐lapse resistivity changes for the first 100 days a...Figure 16.5 Layout of monitoring system at the Vrøgum CO₂ injection site (no...Figure 16.6 Time‐lapse electrical conductivity changes along a diagonal cros...Figure 16.7 Comparison of (a) GPR‐derived CO₂ gas saturation and (b) ERT‐der...

16 Chapter 17Figure 17.1 Thickness map of the Skade formation with the three injection we...Figure 17.2 (a) and (b) P at year 2070. The vertical solid black lines in...Figure 17.3 (a) σ and (b) Δρ in Γ at year 2070.Note that Ω is outlined w...Figure 17.4 (a) ζ generated using ; (b) σ, (c) Δρ, and (d) V _p models mad...Figure 17.5 Step 1 CSEM inversion: (a) True σ, mean of the (b) initial, and ...Figure 17.6 Step 1 CSEM inversion: Variance of the (a) initial and (b) final...Figure 17.7 Step 1 gravity inversion: (a) True Δρ, mean of the (b) initial, ...Figure 17.8 Step 1 gravity inversion: Variance of the (a) initial and (b) fi...Figure 17.9 AVO_w inversion: (a) True V _p , mean of the (b) initial, and (c)...Figure 17.10 AVO_w inversion: Variance of the (a) initial and (b) final updat...Figure 17.11 The ζ generated using for (a) AVO_c and (c) AVO_g; and V _p f...Figure 17.12 AVO_c inversion: (a) True V _p , mean of the (b) initial, and (c...Figure 17.13 AVO_c inversion: Variance of the (a) initial and (b) final updat...Figure 17.14 AVO_g inversion: (a) True V _p , mean of the (b) initial, and (c...Figure 17.15 AVO_g inversion: Variance of the (a) initial and (b) final updat...Figure 17.16 Data misfit using initial ensemble from (a) AVO_w; and final upd...Figure 17.A1 Two arbitrary instances of the LSR with N _c = 2.Figure 17.A2 (a) Schematic detail of parameter grid (thick lines) and forwar...Figure 17.A3 Sketch of arbitrary q(x; m) in the vicinity of ζ: (a) LSR and (...

17 Chapter 18Figure 18.1 Salinity dependence of zeta potential (ζ). In the numerical simu...Figure 18.2 Relative streaming potential coefficient (C _r ) given by equati...Figure 18.3 Schematic representation of a geobattery.Figure 18.4 Three dimensional model used for reservoir simulation of CO₂ inj...Figure 18.5 Histories of total, gaseous, and dissolved CO₂ masses (a) in the...Figure 18.6 Pressure (blue), salinity (green), and CO₂ gas saturation (black...Figure 18.7 Self‐potential distribution produced through electrokinetic coup...Figure 18.8 Distributions of electrical conductivity (left), exchange curren...Figure 18.9 Self‐potential profile produced through the geobattery mechanism...Figure 18.10 Layout of SP monitoring network at the Aneth CCU/EOR test site....Figure 18.11 Measured self‐potentials from May 2008 to May 2010 for (a) thre...Figure 18.12 Layout of SP monitoring near the wellhead of monitoring well at...Figure 18.13 Measured self‐potentials from April 2014 through February 2017 ...

18 Chapter 19Figure 19.1 Location of IBDP (blue star) in relation to Illinois Basin and s...Figure 19.2 Historic and instrument‐located earthquakes in Illinois from 179...Figure 19.3 Geologic column of the IBDP site showing Mt. Simon reservoir, se...Figure 19.4 Aerial site photo view with well locations.Figure 19.5 Cross section across the IBDP study site showing the Mt. Simon a...Figure 19.6 Diagram of pressure readings in lower six levels (zones) of VW1 ...Figure 19.7 Diagram showing configuration of borehole and monitoring equipme...Figure 19.8 (a) Geiger solution RMS residual slice for a selected constraine...Figure 19.9 Maximum theoretical uncertainty of microseismic x‐y‐z location a...Figure 19.10 Sample spectral analysis of data from CCS1 used to compute even...Figure 19.11 Clusters 1–4 directions in relation to maximum horizontal in si...Figure 19.12 Gutenberg‐Richter plot of all the microseismicity during the 3 ...Figure 19.13 (a) FPS inclination analysis using strike‐slip model with avera...Figure 19.14 FPS results for all clusters.Figure 19.15 Key model components and data sources: 3D seismic intersection,...Figure 19.16 (a) Discrete features inverted from microseismic observations u...Figure 19.17 Location of modeled microseismic events (yellow) and measured m...Figure 19.18 Number of modeled microseismic events (green) and observed micr...Figure 19.19 Comparison of modeled microseismic events (red) at time steps t...

19 Chapter 20Figure 20.1 (a) U.S Department of Energy Regional Carbon Sequestration Partn...Figure 20.2 Map showing anthropogenic sources of CO₂ and potential oilfield ...Figure 20.3 Over 150 km of pipeline connect two sources to three projects an...Figure 20.4 Map showing data collection locations and methods for use in cha...Figure 20.5 Geologic characterization of the reservoir occurred at a variety...Figure 20.6 The storage reservoir characterized by hydraulic flow units. HFU...Figure 20.7 Relative strength of reservoir and caprock facies. Caprock facie...Figure 20.8 1,524 m x 1,524 m 1D mechanical Earth model. The model is center...Figure 20.9 Location map of all FWU wells and SWP aqueous‐phase (purple shad...Figure 20.10 Fluid injection and fluid/tracer production history for FWU inj...Figure 20.11 Fluid injection and fluid/tracer production history for FWU inj...Figure 20.12 CO₂ mole fraction 20 year forecast distribution at the FWU. Pla...Figure 20.13 Risk assessment workflow.Figure 20.14 Process influence diagram for CO₂ storage and CO₂‐EOR risks/FEP...Figure 20.15 Monthly accounting since SWP began monitoring the site in 2013,...Figure 20.16 Cumulative values for features shown in Figure 20.15. Targeted ...Figure 20.17 Monthly oil production and CO₂ injection. Oil production and CO

20 Chapter 21Figure 21.1 Location maps showing (a) the regional setting of Cranfield fiel...Figure 21.2 Baseline seismic showing (a) a 30 Hz amplitude variation with fr...Figure 21.3 Comparing the fluid‐flow model to the 4D seismic response (from ...Figure 21.4 Interpreted cross‐well tomography velocity difference at the DAS...Figure 21.5 Inversion of ERT response over time to CO₂ saturation (from Carr...Figure. 21.6 Surface pressure measurements in injection well F1 and observat...

21 Chapter 22Figure 22.1 (a) Location of the Sleipner Field in the Norwegian North Sea. S...Figure 22.2 P‐wave velocity variation with brine saturation for various patc...Figure 22.3 Two‐way travel time map view of the Top Utsira Sand Wedge horizo...Figure 22.4 (a) P‐wave velocity model of baseline vintage (1994) derived by ...Figure 22.5 (a, b, and c) Frame bulk modulus K_D, frame shear modulus G_D, and...Figure 22.6 (a, b, and c) Uncertainty of frame bulk modulus K_D, frame shear ...Figure 22.7 (a, b, and c) CO₂ saturation estimated by RPI using patchiness e...Figure 22.8 (a, b, and c) Uncertainty of CO₂ saturation estimated by RPI usi...Figure 22.9 (a and b) Estimation of patchiness exponent and related uncertai...Figure 22.10 From left to right: 1D profiles of CO₂ saturation using differe...Figure 22.11 Estimation of frame shear modulus, frame bulk modulus, and poro...Figure 22.12 (a and b) Estimation of brine saturation S_w and (c and d) estim...Figure 22.13 Estimation of brine saturation S_w and Brie exponent e in the ca...Figure 22.14 Estimation of brine saturation S_w and Brie exponent e in the ca...

22 Chapter 23Figure 23.1 Annual CO₂ emission per capita in 2010 (data after Worldbank) an...Figure 23.2 Location and structural model of the Ketzin site. (a) location o...Figure 23.3 Drilled lithological profiles of the Stuttgart Formation as reco...Figure 23.4 Normalized logging data for the injection well Ktzi201 showing (...Figure 23.5 Reservoir pressure (top) and temperature (middle) evolution and ...Figure 23.6 Thermodynamic path of the CO₂ during normal operation with event...Figure 23.7 (a) Electrical resistivity of two Ketzin reservoir sandstone sam...Figure 23.8 Time line of geophysical survey activities at the Ketzin site (d...Figure 23.9 Overview of investigations relevant for the geophysical monitori...Figure 23.10 (a) Outlines of the baseline (black), the first repeat 3D (red)...Figure 23.11 Cross‐section of the stacked and migrated subvolume of the base...Figure 23.12 Amplitude difference (baseline‐repeat) maps at the reservoir le...Figure 23.13 Acoustic impedances inverted from (a) baseline, (b) first repea...Figure 23.14 P‐wave velocities derived from impedance inversion of the 3D ba...Figure 23.15 Relative velocity changes between baseline measurements and fir...Figure 23.16 Sparse 3D seismic survey area with the system of 3D inlines and...Figure 23.17 Amplitude difference horizon at the reservoir level for (a) the...Figure 23.18 Comparison of inverted velocity change percentage for 3D seismi...Figure 23.19 Comparison of the Fresnel depth migration of offset VSP source ...Figure 23.20 (a) Velocity differences obtained by travel time inversion and ...Figure 23.21 Inverted seismic velocity differences (baseline‐repeat) between...Figure 23.22 Layout and location of the permanent geophone/hydrophone array....Figure 23.23 (a) Smoothed frequency spectrum and (b) amplitude decay curve f...Figure 23.24 Inline 1,175 of the 3D seismic data (Juhlin et al., 2007), on w...Figure 23.25 (a) Borehole casing electrically insulated with Ryt‐Wrap™ (dark...Figure 23.26 (a) Time‐lapse sequence of inverted resistivity ratios (i.e., m...Figure 23.27 (a) Series of resistivity images obtained from surface‐downhole...Figure 23.28 (a) Time‐lapse electrical resistivity anomaly and (b) time‐laps...