Combination of surface and borehole seismic data for robust target-oriented imaging

Liu, Yi; Neut, Joost van der; Arntsen, Børge; Wapenaar, Kees

doi:10.1093/gji/ggw011

Cited by 17 publications

(11 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this case, the reflected wavefield from below the target has the potential to enrich the illumination in the image from below, as discussed before. Moreover, the kinematic variations in Figure 6a and 6b confirm previous studies with physical receivers in boreholes (Liu et al, 2016) and could be used to update the propagation velocity model, as suggested elsewhere in the literature (Ravasi et al, 2015b). When the multidimensional Marchenko equation is used to retrieve the wavefields at the lower array, such velocity updates seem impossible, as confirmed by Figure 6c and 6d, where kinematic variations cannot be observed.…”

Section: Target-enclosed Seismic Imaging Q63supporting

confidence: 84%

Target-enclosed seismic imaging

et al. 2017

Self Cite

View full text Add to dashboard Cite

Seismic reflection data can be redatumed to a specified boundary in the subsurface by solving an inverse (or multidimensional deconvolution) problem. The redatumed data can be interpreted as an extended image of the subsurface at the redatuming boundary, depending on the subsurface offset and time. We retrieve target-enclosed extended images by using two redatuming boundaries, which are selected above and below a specified target volume. As input, we require the upgoing and downgoing wavefields at both redatuming boundaries due to impulsive sources at the earth’s surface. These wavefields can be obtained from actual measurements in the subsurface, they can be numerically modeled, or they can be retrieved by solving a multidimensional Marchenko equation. As output, we retrieved virtual reflection and transmission responses as if sources and receivers were located at the two target-enclosing boundaries. These data contain all orders of reflections inside the target volume but exclude all interactions with the part of the medium outside this volume. The retrieved reflection responses can be used to image the target volume from above or from below. We found that the images from above and below are similar (given that the Marchenko equation is used for wavefield retrieval). If a model with sharp boundaries in the target volume is available, the redatumed data can also be used for two-sided imaging, where the retrieved reflection and transmission responses are exploited. Because multiple reflections are used by this strategy, seismic resolution can be improved significantly. Because target-enclosed extended images are independent on the part of the medium outside the target volume, our methodology is also beneficial to reduce the computational burden of localized inversion, which can now be applied inside the target volume only, without suffering from interactions with other parts of the medium.

show abstract

Section: Target-enclosed Seismic Imaging Q63supporting

confidence: 84%

Target-enclosed seismic imaging

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…In case the measured direct arrival is not satisfactory, some interpolation based on the existing traveltime curve can be used without using a velocity model. Furthermore, in case the focusing function cannot be found, approximate solutions (Liu et al, 2016) to the desired reflection responses are still sufficient for evaluating the changes close to the borehole, except that the multiples are not completely removed in that case. The added advantage of using the Marchenko scheme allows the retrieval of the reflection response using single-component data without any multiples from the other side of the borehole.…”

Section: Discussionmentioning

confidence: 99%

“…However, velocity errors in the model affect the method to various degrees (Thorbecke et al, 2013;de Ridder et al, 2016). For the method's application for robust imaging near horizontal boreholes, Liu et al (2016) propose the combination of surface reflection data and horizontal borehole data to replace the dependency on a background velocity model. Two separate reflection responses can be obtained, one for the overburden and one for the underburden (the area below a horizontal borehole, including the reservoir).…”

Section: Introductionmentioning

confidence: 99%

“…By repeating two of the proposed schemes in Liu et al (2016) on the base and monitor data, the time shifts in the overburden and the underburden can be separated and subtle time shifts near the horizontal borehole can be estimated without any event picking on the data. Then, standard time shift analysis can be performed for each side of the borehole independently.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A new approach to separate seismic time-lapse time shifts in the reservoir and overburden

et al. 2017

Self Cite

View full text Add to dashboard Cite

For a robust way of estimating time shifts near horizontal boreholes, we have developed a method for separating the reflection responses above and below a horizontal borehole. Together with the surface reflection data, the method uses the direct arrivals from borehole data in the Marchenko method. The first step is to retrieve the focusing functions and the updown wavefields at the borehole level using an iterative Marchenko scheme. The second step is to solve two linear equations using a least-squares minimizing method for the two desired reflection responses. Then, the time shifts that are directly linked to the changes on either side of the borehole are calculated using a standard crosscorrelation technique. The method is applied with good results to synthetic 2D pressure data from the North Sea. One example uses purely artificial velocity changes (negative above the borehole and positive below), and the other example uses more realistic changes based on well logs. In the 2D case with an adequate survey coverage at the surface, the method is completely data driven. In the 3D case in which there is a limited number of horizontal wells, a kinematic correct velocity model is needed, but only for the volume between the surface and the borehole. Possible error factors related to the Marchenko scheme, such as an inaccurate source wavelet, imperfect surface multiples removal, and medium with loss are not included in this study.

show abstract

“…Vasconcelos et al (2015) demonstrate the effectiveness of the methodology in complex media and illustrate how prior knowledge of the medium's reflectivity can be integrated. Liu et al (2016) use the Marchenko equation for local imaging below and above a borehole by combining seismic records at the surface with vertical seismic profile data. Although we restrict ourselves to solutions of the acoustic-wave equation in this paper, the Marchenko equation can also be derived for elastic media (da Costa Filho et al, 2014Wapenaar and Slob, 2014).…”

Section: Introductionmentioning

confidence: 99%

Adaptive overburden elimination with the multidimensional Marchenko equation

2016

Self Cite

View full text Add to dashboard Cite

Iterative substitution of the multidimensional Marchenko equation has been introduced recently to integrate internal multiple reflections in the seismic imaging process. In so-called Marchenko imaging, a macro velocity model of the subsurface is required to meet this objective. The model is used to back-propagate the data during the first iteration and to truncate integrals in time during all successive iterations. In case of an erroneous model, the image will be blurred (akin to conventional imaging) and artifacts may arise from inaccurate integral truncations. However, the scheme is still successful in removing artifacts from internal multiple reflections. Inspired by these observations, we rewrote the Marchenko equation, such that it can be applied early in a processing flow, without the need of a macro velocity model. Instead, we have required an estimate of the two-way traveltime surface of a selected horizon in the subsurface. We have introduced an approximation, such that adaptive subtraction can be applied. As a solution, we obtained a new data set, in which all interactions (primaries and multiples) with the part of the medium above the picked horizon had been eliminated. Unlike various other internal multiple elimination algorithms, the method can be applied at any specified target horizon, without having to resolve for internal multiples from shallower horizons. We successfully applied the method on synthetic data, where limitations were reported due to thin layers, diffraction-like discontinuities, and a finite acquisition aperture. A field data test was also performed, in which the kinematics of the predicted updates were demonstrated to match with internal multiples in the recorded data, but it appeared difficult to subtract them.

show abstract

Combination of surface and borehole seismic data for robust target-oriented imaging

Cited by 17 publications

References 41 publications

Target-enclosed seismic imaging

Target-enclosed seismic imaging

A new approach to separate seismic time-lapse time shifts in the reservoir and overburden

Adaptive overburden elimination with the multidimensional Marchenko equation

Contact Info

Product

Resources

About