scholarly journals Using image warping for time-lapse image domain wavefield tomography

Geophysics ◽  
2014 ◽  
Vol 79 (3) ◽  
pp. WA141-WA151 ◽  
Author(s):  
Di Yang ◽  
Alison Malcolm ◽  
Michael Fehler
Keyword(s):  
Cost Function ◽  
Oil And Gas ◽  
Waveform Inversion ◽  
Time Lapse ◽  
Gas Production ◽  
Reservoir Properties ◽  
Image Domain ◽  
Seismic Waveform ◽  
Realistic Situation ◽  
Velocity Changes

Time-lapse seismic data are widely used for monitoring subsurface changes. A quantitative assessment of how reservoir properties have changed allows for better interpretation of fluid substitution and fluid migration during processes such as oil and gas production and carbon sequestration. Full-waveform inversion (FWI) has been proposed as a way to retrieve quantitative estimates of subsurface properties through seismic waveform fitting. However, for some monitoring systems, the offset range versus depth of interest is not large enough to provide information about the low-wavenumber component of the velocity model. We evaluated an image domain wavefield tomography (IDWT) method using the local warping between baseline and monitor images as the cost function. This cost function is sensitive to volumetric velocity anomalies, and it is capable of handling large velocity changes with very limited acquisition apertures, where traditional FWI fails. We described the theory and workflow of our method. Layered model examples were used to investigate the performance of the algorithm and its robustness to velocity errors and acquisition geometry perturbations. The Marmousi model was used to simulate a realistic situation in which IDWT successfully recovers time-lapse velocity changes.

Combining reflection and transmission information in time-lapse velocity inversion: A new hybrid approach

Geophysics ◽  
2019 ◽  
Vol 84 (4) ◽  
pp. R601-R611 ◽  
Author(s):  
Maria Kotsi ◽  
Jonathan Edgar ◽  
Alison Malcolm ◽  
Sjoerd de Ridder
Keyword(s):  
Waveform Inversion ◽  
Hybrid Approach ◽  
Time Lapse ◽  
Velocity Model ◽  
Nonlinear Inversion ◽  
Image Domain ◽  
Velocity Inversion ◽  
Reflected Waves ◽  
Deep Diving ◽  
Velocity Changes

Full-waveform inversion (FWI) uses the information of the full wavefield to deliver high-resolution images of the subsurface. Conventional time-lapse FWI primarily uses the transmitted component (diving waves) of the wavefield to reconstruct the low-wavenumber component of the velocity model. This requires large-offset surveys and low-frequency data. When the target of interest is deep, diving waves cannot reach the target and FWI will be dominated by the reflected component of the wavefield. Consequently, the retrieved model resembles a least-squares migration instead of a velocity model. Image-domain methods, especially image-domain wavefield tomography (IDWT), have been developed to obtain a model of time-lapse velocity changes in deeper targets using reflected waves. The method is able to recover models of deep targets. However, it also tends to obtain smeared time-lapse velocity changes. We have developed a form of time-lapse waveform inversion that we call dual-domain time-lapse waveform inversion (DDWI), whose objective function joins FWI and IDWT, combining information from the diving waves in the data-domain FWI term with information from the reflected waves in the image-domain IDWT term. During the nonlinear inversion, the velocity model is updated using constraints from both terms simultaneously. Similar to sequential time-lapse waveform inversion, we start the time-lapse inversion from a baseline model recovered with FWI. We test DDWI on a variety of synthetic models of increasing complexity and find that it can recover time-lapse velocity changes more accurately than when both methods are used independently or sequentially.

Comparative analysis of production potential in Bulla-deniz and Umid gas-condensate fields

2020 ◽  
pp. 21-26
Author(s):  
E.H. Ahmadov ◽  
Keyword(s):  
Oil And Gas ◽  
Reduction Rate ◽  
Chemical Properties ◽  
Gas Production ◽  
Layer System ◽  
Reservoir Properties ◽  
Technical Parameters ◽  
Recovery Curves ◽  
Well Model ◽  
Drilling Technology

The paper studies the reduction rate of gas production in the wells of Bulla-deniz field drilled to VIII horizon. With this purpose, geological (reservoir properties, oil-gas saturation, net thickness, formation pressure and temperature, formation heterogeneity, multi-layer system, tectonic faults, physical-chemical properties of oil and gas etc.) and technological (well structure, measuring and transportation system, well operation regime, drilling technology etc.) conditions of formation were analyzed and the well model of VII and VIII horizons of Bulla-deniz field using these geological and technical parameters developed as well. For the estimation of impact of geological and technical aspects on production, sensitivity analysis was carried out on the models. The suggestions for elaboration of uncertainty of geological and technical parameters affecting production dynamics were developed. To reveal the reasons for production differences of the wells, it was proposed to install borehole manometers, to obtain the data on pressure recovery curves, drainage area, skin-effect impact, permeability and to develop a study plan of bottomhole zone with acid.

Data-driven Prestack Waveform Inversion Using Genetic Algorithm- Methodology and Examples

2021 ◽  
pp. 1-97
Author(s):  
Lingxiao Jia ◽  
Subhashis Mallick ◽  
Cheng Wang
Keyword(s):  
Genetic Algorithm ◽  
Seismic Data ◽  
Waveform Inversion ◽  
Seismic Inversion ◽  
P Wave ◽  
Data Driven ◽  
Initial Model ◽  
Reservoir Properties ◽  
Well Control ◽  
Seismic Waveform

The choice of an initial model for seismic waveform inversion is important. In matured exploration areas with adequate well control, we can generate a suitable initial model using well information. However, in new areas where well control is sparse or unavailable, such an initial model is compromised and/or biased by the regions with more well controls. Even in matured exploration areas, if we use time-lapse seismic data to predict dynamic reservoir properties, an initial model, that we obtain from the existing preproduction wells could be incorrect. In this work, we outline a new methodology and workflow for a nonlinear prestack isotropic elastic waveform inversion. We call this method a data driven inversion, meaning that we derive the initial model entirely from the seismic data without using any well information. By assuming a locally horizonal stratification for every common midpoint and starting from the interval P-wave velocity, estimated entirely from seismic data, our method generates pseudo wells by running a two-pass one-dimensional isotropic elastic prestack waveform inversion that uses the reflectivity method for forward modeling and genetic algorithm for optimization. We then use the estimated pseudo wells to build the initial model for seismic inversion. By applying this methodology to real seismic data from two different geological settings, we demonstrate the usefulness of our method. We believe that our new method is potentially applicable for subsurface characterization in areas where well information is sparse or unavailable. Additional research is however necessary to improve the compute-efficiency of the methodology.

Joint time-lapse full-waveform inversion with a time-lag cost function

2021 ◽  
Author(s):  
Zhiguang Xue ◽  
Zhigang Zhang ◽  
Ping Wang ◽  
Jun Cai
Keyword(s):  
Cost Function ◽  
Time Lag ◽  
Waveform Inversion ◽  
Time Lapse ◽  
Full Waveform Inversion ◽  
Full Waveform

Time-lapse full-waveform inversion of limited-offset seismic data using a local migration regularization

Geophysics ◽  
2014 ◽  
Vol 79 (3) ◽  
pp. WA117-WA128 ◽  
Author(s):  
Espen Birger Raknes ◽  
Børge Arntsen
Keyword(s):  
Waveform Inversion ◽  
Estimation Algorithm ◽  
Time Lapse ◽  
Full Waveform Inversion ◽  
Local Contrast ◽  
Image Domain ◽  
Full Waveform ◽  
Conventional Methods ◽  
Offset Time ◽  
Elastic Inversion

Conventional methods for quantifying time-lapse seismic effects rely on a linear assumption that is easily violated. Therefore, more sophisticated methods are necessary. The full-waveform inversion (FWI) method is an inverse method that is able to reveal time-lapse changes in the image domain, in which the conventional methods break down. We investigated the behavior of FWI using different approaches for applying FWI on limited-offset time-lapse data. We compared acoustic and elastic inversion schemes. We introduced a method for constraining the model update for the monitor model to remove time-lapse artifacts. This method was based on migration of the residuals in the time-lapse data, which, in combination with a local contrast estimation algorithm, formed the update constraint. We found that for limited-offset data, elastic theory was necessary for the success of FWI and that FWI was able to quantify the time-lapse changes in the parameter models. The local migration regularization approach was able to remove time-lapse artifacts.

Time-lapse inverse theory with applications

Geophysics ◽  
2016 ◽  
Vol 81 (6) ◽  
pp. R485-R501 ◽  
Author(s):  
Musa Maharramov ◽  
Biondo L. Biondi ◽  
Mark A. Meadows
Keyword(s):  
Waveform Inversion ◽  
Significant Risk ◽  
Time Lapse ◽  
Long Wavelength ◽  
Full Waveform ◽  
Total Variation Model ◽  
Velocity Anomalies ◽  
Velocity Changes ◽  
Primary Focus ◽  
Production Effects

Compaction in the reservoir overburden can impact production facilities and lead to a significant risk of well-bore failures. Prevalent practices of time-lapse seismic processing of 4D data above compacting reservoirs rely on picking time displacements and converting them into estimated velocity changes and subsurface deformation. This approach relies on prior data equalization and requires a significant amount of manual interpretation and quality control. We have developed methods for automatic detection of production-induced subsurface velocity changes from seismic data. We have evaluated a time-lapse inversion technique based on a simultaneous regularized full-waveform inversion (FWI) of multiple surveys. In our approach, baseline and monitor surveys are inverted simultaneously with a model-difference regularization penalizing nonphysical differences in the inverted models that are due to survey or computational repeatability issues. The primary focus of our work was the inversion of long-wavelength “blocky” changes in the subsurface model, and this was achieved using a phase-only FWI with a total-variation model-difference regularization. However, we have developed a multiscale extension of our method for recovering long- and short-wavelength production effects. We have developed a theoretical foundation of our method and analyzed its sensitivity to a realistic 1%–2% velocity deformation. The method was applied in a study of overburden dilation above the Gulf of Mexico Genesis field and recovered blocky negative-velocity anomalies above compacting reservoirs.

scholarly journals Synergetics of geological mediums and its impact on the effectiveness of the exploitation and exploration for mineral deposits

2019 ◽  
pp. 15-21
Author(s):  
Yu. I. Voitenko
Keyword(s):  
Gas Flow ◽  
Oil And Gas ◽  
Solid Phase ◽  
Dynamic Effect ◽  
Gas Production ◽  
Reservoir Properties ◽  
Uniform Compression ◽  
Reduced Pressure ◽  
Oil And Gas Production ◽  
Joint Influence

The mechanisms of joint influence of mountain and reservoir pressures, saturating fluid, structure elements of rocks and external dynamic effects on their behavior in natural conditions, in particular near of the well, are investigated. With specific examples, it is shown that the behavior of rocks with such a set of influencing factors is determined by the laws of synergetics and the combined action of external influences, uneven stress-strain state of the rocks, the pore pressure and chemo mechanical effects. Examples are the results of gas-flow and gas-metric studies of closed wells, as well as the results of explosive perforation and intensification of producing wellbores at different depths. Defects occurrence in minerals with a high modulus of elasticity is initiated by an external dynamic effect and independently under the action of the saturating fluid. Then, under volumetric non-uniform compression and reservoir pressure, gradual fracturing of terrigenous rocks occurs at the micro and macro level. The result of these processes is the formation of areas of the improved permeability near the wells during drilling, production and suspending. When drilling on traditional technology they will impair formation reservoir properties via infiltration of water and solid phase. In oil and gas wells and in closed wells - improve these properties. Analysis of the behavior of rocks from the synergetic position shows that the best mode of loading on the reservoir during wells drilling, wells completion and oil and gas production is depression (reduced pressure) on the reservoir. The known and new promising technologies for the intensification of oil and gas production are determined.

scholarly journals True-amplitude migration through regularized extended linearized waveform inversion

Geophysics ◽  
2021 ◽  
pp. 1-138
Author(s):  
Ettore Biondi ◽  
Mark A. Meadows ◽  
Biondo Biondi
Keyword(s):  
Oil And Gas ◽  
Reservoir Characterization ◽  
Waveform Inversion ◽  
Elastic Behavior ◽  
Ocean Bottom ◽  
Reverse Time ◽  
Image Domain ◽  
Oil And Gas Exploration ◽  
Single Interface ◽  
Time Migration

The ability to create subsurface images whose amplitudes are proportional to the elastic wavefield variations recorded within seismic data as a function of reflection angle is fundamental for performing accurate amplitude-versus-offset (AVO) analysis and inversion. A process that generates such images is commonly referred to as true-amplitude migration. We demonstrate how the extended subsurface-offset image space is able to preserve the elastic behavior of the primary reflections when these events are acoustically migrated with a reverse-time-migration (RTM) approach performed in a least-squares fashion. Using a single-interface model, we show how the angle-domain image amplitude variations from an extended-offset acoustically migrated image closely follow the theoretical elastic Zoeppritz response even at the critical angle. Furthermore, we present a subsalt synthetic test in which single-component ocean-bottom-node (OBN) data are employed within a regularized linearized waveform inversion procedure. In this test, we highlight the ability of the acoustic extended-angle image domain to preserve the correct elastic amplitude variations of the reflected events from three subsalt sand lenses. The proposed method allows the accurate inversion of elastic-wave data for subsurface parameter variations that are critical for reservoir characterization in oil and gas exploration and production. We demonstrate its performance on an ocean-bottom-node (OBN) field dataset recorded in the Gulf of Mexico in which the AVO response of a potential gas-bearing prospect is correctly retrieved.

Sign in / Sign up

Export Citation Format

Share Document