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Seismic acquisition design based on full-wavefield migration

Revelo Obando, B.A. (author), Blacquière, G. (author)

The ultimate goal in survey design is to obtain the acquisition parameters that enable acquiring the most affordable data that fulfills certain image quality requirements. We propose a method that allows optimization of the receiver geometry for a fixed source distribution. The former is parameterized with a receiver density function that...

journal article 2023

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Source deghosting of coarsely sampled common-receiver data using a convolutional neural network

Vrolijk, J. (author), Blacquière, G. (author)

It is well known that source deghosting can best be applied to common-receiver gathers, whereas receiver deghosting can best be applied to common-shot records. The source-ghost wavefield observed in the common-shot domain contains the imprint of the subsurface, which complicates source deghosting in the common-shot domain, in particular when the...

journal article 2021

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Acquisition geometry analysis with point-spread functions

Revelo Obando, B.A. (author), Blacquière, G. (author)

Seismic data are traditionally acquired based on spatial sampling requirements, noise properties and budgetary constraints. However, designing a survey without taking into account the complexity of the subsurface may result in an image without the expected quality. Also, the subsequent preprocessing and processing steps may exploit or misuse...

journal article 2021

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Automated seismic acquisition geometry design for optimized illumination at the target: a linearized approach

Wu, S. (author), Verschuur, D.J. (author), Blacquière, G. (author)

In seismic exploration methods, imperfect spatial sampling at the surface causes a lack of illumination at the target in the subsurface. The hampered image quality at the target area of interest causes uncertainties in reservoir monitoring and production, which can have a substantial economic impact. Especially in the case of a complex...

journal article 2021

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Machine-learning-based data recovery and its contribution to seismic acquisition: Simultaneous application of deblending, trace reconstruction, and low-frequency extrapolation

Nakayama, Shotaro (author), Blacquière, G. (author)

Acquisition of incomplete data, i.e., blended, sparsely sampled, and narrowband data, allows for cost-effective and efficient field seismic operations. This strategy becomes technically acceptable, provided that a satisfactory recovery of the complete data, i.e., deblended, well-sampled, and broadband data, is attainable. Hence, we explore a...

journal article 2021

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Order-controlled closed-loop focal beams and resolution comparison of primary and multiple reflections for seismic acquisition geometries

Wei, Wei (author), Blacquière, G. (author)

Focal beam analysis has built a bridge between the acquisition parameters on the surface and the image quality of underground targets. However, as a practical matter, it is still difficult to answer how to choose a proper acquisition geometry according to the complexity of medium, especially considering the contradictory effects of multiple...

journal article 2021

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Blended acquisition with temporally signatured/modulated and spatially dispersed source array

Ishiyama, Tomohide (author), Ali, Mohammed (author), Blacquière, G. (author), Nakayama, S. (author)

We introduce a blended-acquisition method: temporally signatured and/or modulated and spatially dispersed source array, namely S-/M-DSA. The former S-DSA has much less constraints in the encoding with operational flexibility, allowing non-uniform sampling and non-patterned shooting both in the space and time dimension. The latter M-DSA allows...

conference paper 2019

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Optimum seismic acquisition geometry design with the help of artificial intelligence

Blacquière, G. (author), Nakayama, S. (author)

Acquisition geometry design aims at finding the most affordable acquisition geometry that satisfies the objectives of the seismic survey. The parameters of an acquisition geometry can be specified in terms of the number of sources and detectors, their location, the blending parameters and the DSA (dispersed source array) parameters. In our...

conference paper 2019

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Modeling and assessing the effects of the sea surface, from being flat to being rough and dynamic

Blacquière, G. (author), Sertlek, H.O. (author)

The sea surface acts as a very strong reflector because of the large impedance contrast between water and air. The reflection coefficient is -1 in a very good approximation. Apart from the surface multiples, the sea surface is also responsible for generating the source and receiver ghost wavefields. These cause the well-known ghost notches in...

journal article 2019

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Acquisition design for direct reflectivity and velocity estimation from blended and irregularly sampled data

Nakayama, S. (author), Blacquière, G. (author), Ishiyama, Tomohide (author)

Blended acquisition along with efficient spatial sampling is capable of providing high-quality seismic data in a cost-effective and productive manner. While deblending and data reconstruction conventionally accompany this way of data acquisition, the recorded data can be processed directly to estimate subsurface properties. We establish a...

journal article 2019

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Shot repetition: An alternative seismic blending code in marine acquisition

Wu, S. (author), Blacquière, G. (author), Adriaan Van Groenestijn, Gert Jan (author)

In blended seismic acquisition, or simultaneous source seismic acquisition, source encoding is essential at the acquisition stage to allow for separation of the blended sources at the processing stage. In land seismic surveys, the vibroseis sources may be encoded with near-orthogonal sweeps for blending. In marine seismic surveys, the sweep...

journal article 2018

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3D surface-wave estimation and separation using a closed-loop approach

Ishiyama, T. (author), Blacquière, G. (author), Verschuur, D.J. (author), Mulder, W.A. (author)

Surface waves in seismic data are often dominant in a land or shallow-water environment. Separating them from primaries is of great importance either for removing them as noise for reservoir imaging and characterization or for extracting them as signal for near-surface characterization. However, their complex properties make the surface-wave...

journal article 2016

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3-D shallow-water seismic survey evaluation and design using the focal-beam method: a case study offshore Abu Dhabi

Ishiyama, T. (author), Blacquière, G. (author)

For 3-D shallow-water seismic surveys offshore Abu Dhabi, imaging the target reflectors requires high resolution. Characterization and monitoring of hydrocarbon reservoirs by seismic amplitude-versus-offset techniques demands high pre-stack amplitude fidelity. In this region, however, it still was not clear how the survey parameters should be...

journal article 2016

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Deghosting by echo-deblending

Berkhout, A.J. (author), Blacquiere, G. (author)

Because of the strong sea surface reflectivity, a marine source generates both a direct wavefield and a ghost wavefield. This corresponds to a blended source array, the blending process being natural. Consequently, deghosting becomes deblending ('echo-deblending'). We discuss source deghosting by an iterative deblending algorithm that properly...

conference paper 2015

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Using Ghost Reflections Rather than Removing Them

Blacquiere, G. (author), Berkhout, A.J. (author)

In marine acquisition both a direct wavefield and a ghost wavefield are produced as well as recorded. Hence, the seismic data can be considered to be a natural blend of four wavefields related to the real sources, ghost sources, real detectors and ghost detectors respectively. We consider deghosting to be deblending ('echo-deblending'), leading...

conference paper 2015

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Broadband seismic by means of dispersed source arrays

Caporal, M. (author), Blacquiere, G. (author)

Seismic sources deployed during a particular survey are historically chosen to be equal. However, from a physical point of view the constraint of using only identical source units is not required. We suggest to abandon this constraint and to replace, or reinforce, traditional broadband sources with narrower-band devices, together representing a...

conference paper 2015

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Marine survey design and analysis using all multiples

Kumar, A. (author), Blacquiere, G. (author), Pedersen, M.W. (author), Goertz, A. (author)

Despite a tremendous leap in efficiency and wave field sampling over the last two decades, it is sometimes still difficult to achieve adequate coverage and resolution with marine streamer acquisition. It is therefore necessary to carefully study the acquisition geometry, especially with respect to resolution and image quality in the cross-line...

conference paper 2015

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The impact of surface-wave separation on seismic survey design

Ishiyama, T. (author), Blacquiere, G. (author), Mulder, W.A. (author)

3-D seismic survey design provides an acquisition geometry for obtaining seismic data that enable imaging and amplitude-versus-offset applications of target reflectors with sufficient quality under given economical and operational constraints. However, in land or shallow water environments, surface waves are often dominant and will lower the...

conference paper 2015

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Benefits of blended acquisition with dispersed source arrays (DSA)

Caporal, M. (author), Blacquiere, G. (author)

In blended data acquisition, the recorded wave field is incoherent. Nevertheless blended source units in the arrays are historically chosen to be equal. We propose to abandon this constraint. This allows us to suggest the exploitation of inhomogeneous blended sources, together representing a Dispersed Source Array (DSA). Each source unit...

conference paper 2015

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Toward the limits of deblending

Berkhout, A.J. (author), Blacquiere, G. (author)

If we bring sources closer together, they start to `sense' the nearness of each other and their physical behaviour will change. If the separation becomes smaller than half a wavelength, they start to act as one source with new properties (temporal bandwidth, directivity). This fusion process is very complex and nonlinear. To find out whether...

conference paper 2015