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Exact 3D seismic data reconstruction using Tubal-Alt-Min algorithm Feng Qian 1 , Quan Chen 2 , Ming-Jun Su 3 , Guang-Min Hu 2 , Xiao-Yang Liu * 1 Center of Information Geoscience, University of Electronic Science and Technology of China, 2 School of Rresources and Environment, University of Electronic Science and Technology of China, 3 PetroChina Research Institute of Petroleum Exploration and Development (RIPED)-Northwest, Lanzhou, China, * Department of Electrical Engineering, Columbia University, NY, USA SUMMARY Data missing is an common issue in seismic data, and many methods have been proposed to solve it. In this paper, we present the low-tubal-rank tensor model and a novel tensor completion algorithm to recover 3D seismic data. This is a fast iterative algorithm, called Tubal-Alt-Min which completes our 3D seismic data by exploiting the low-tubal-rank property expressed as the product of two much smaller tensors. Tubal- Alt-Min alternates between estimating those two tensor using least squares minimization. We evaluate its reconstruction per- formance both on synthetic seismic data and land data sur- vey. The experimental results show that compared with the tensor nuclear norm minimization algorithm, Tubal-Alt-Min improves the reconstruction error by orders of magnitude. INTRODUCTION Seismic data quality is vital to various geophysical process- ing. However, due to the financial and physical constraints, the real seismic survey data are usually incomplete. Seismic data reconstruction is a complex problem, and a large number of researchers have devoted themselves to the research of this field. Consequently, many approaches have been proposed to handle this problem. From the point of view of data organiza- tion, these methods can be divided into two categories. The low dimensional based methods, such as transform-based methods which utilize the properties of the seismic trace in an auxiliary domain (Hennenfent et al., 2010). Liner prediction theory use the predictability of the signal in the f-x or t-x do- main (Naghizadeh and Sacchi, 2007). And methods which ex- ploit the low-rank nature of seismic data embedded in Hankel matrices (Oropeza and Sacchi, 2011). Those low dimensional based methods usually ignores the spa- tial structure of the seismic traces. While the spatial struc- ture coherence is very important for the seismic data comple- tion, hence recent developments in high dimensional tensor completion approaches exploit various tensor decomposition model are widely used in seismic data reconstruction (Kreimer et al., 2013; Ely et al., 2015a). Those high-order tensor de- composition approaches have became a trend for seismic data completion, and the exist different definitions for tensor de- composition that lead to different tensor completion model, i.e. the higher-order singular value decomposition (HOSVD) (Kreimer and Sacchi, 2011), the tuker decomposition (Da Silva and Herrmann, 2013), and tensor SVD (tSVD) decomposition (Ely et al., 2015b). In this paper, we focus on a new seismic data reconstruction algorithm which based on low-tubal-rank tensor decomposi- tion model possesses extremely high precision seismic data recovery performance. Because of the high redundancy or co- herence between one seismic trace to the others (Ely et al., 2015a), we assume that the fulled sampled seismic volume has low-tubal-rank property in the tSVD domain. Therefore, we can solve the seismic tensor completion problem through an alternating minimization algorithm for low-tubal-rank tensor completion (Tubal-Alt-Min) (Liu et al., 2016a,b). We have evaluated the performance of this approach on both synthetic and field seismic data. NOTATIONS The data in seismic survey is a natural high-dimensional ten- sor, such as the 3D poststack seismic data which consists of one time or frequency dimension and two spatial dimensions corresponding to xline and inline directions. Throughout the paper, we denote those 3D seismic tensor in time domain by uppercase calligraphic letter, T R m×n×k , and denote the frequency domain 3D seismic tensor by e T R m×n×k correspondingly. Uppercase letter A R m×n denotes matrix, and lowercase boldface letter x R n denotes vector. Let [n] denotes the set {1, 2,..., n}. In addition, we introduce an important tensor operator t-product (Kilmer et al., 2013). t-product. The tensor-product T = X * Y of X R n 1 ×n 2 ×k and Y R n 2 ×n 3 ×k is a tensor of size n 1 × n 2 × k, T (i, j, :)= n 2 s=1 X (i, s, :) * Y (s, j, :), for i [n 1 ] and j [n 3 ]. PROBLEM SETUP From what we have stated above, we know that seismic data comprises many traces that provide a spatio-temporal sam- pling of the reflected wavefield. However, caused by various factors, such lost many important informations. Such as the exist of reservoir, residential or any other obstacle in the seis- mic data acquisition areas will lead to under-sampled seismic record. The missing traces will complicate certain data pro- cessing steps such as the prediction accuracy of underground reservoirs. Hence, the completion step in seismic data process- ing is of grate significance. In this paper, we explored the relationship between low-tubal- rank and under-sampled rate firstly, and found that low-tubal property is positively correlated with the sampling rate. Figure 1 shows the detail experiment result. Base on this work, we as- arXiv:1704.02445v1 [cs.CE] 8 Apr 2017

arXiv:1704.02445v1 [cs.CE] 8 Apr 2017kP W(T) P W(XY)k2F: (2) This cost function can be solved by the alternating minimiza-tion algorithm for low tubal rank tensor completion designed

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Page 1: arXiv:1704.02445v1 [cs.CE] 8 Apr 2017kP W(T) P W(XY)k2F: (2) This cost function can be solved by the alternating minimiza-tion algorithm for low tubal rank tensor completion designed

Exact 3D seismic data reconstruction using Tubal-Alt-Min algorithmFeng Qian1, Quan Chen2, Ming-Jun Su3, Guang-Min Hu2, Xiao-Yang Liu∗1Center of Information Geoscience, University of Electronic Science and Technology of China,2School of Rresources and Environment, University of Electronic Science and Technology of China,3PetroChina Research Institute of Petroleum Exploration and Development (RIPED)-Northwest, Lanzhou, China,∗Department of Electrical Engineering, Columbia University, NY, USA

SUMMARY

Data missing is an common issue in seismic data, and manymethods have been proposed to solve it. In this paper, wepresent the low-tubal-rank tensor model and a novel tensorcompletion algorithm to recover 3D seismic data. This is afast iterative algorithm, called Tubal-Alt-Min which completesour 3D seismic data by exploiting the low-tubal-rank propertyexpressed as the product of two much smaller tensors. Tubal-Alt-Min alternates between estimating those two tensor usingleast squares minimization. We evaluate its reconstruction per-formance both on synthetic seismic data and land data sur-vey. The experimental results show that compared with thetensor nuclear norm minimization algorithm, Tubal-Alt-Minimproves the reconstruction error by orders of magnitude.

INTRODUCTION

Seismic data quality is vital to various geophysical process-ing. However, due to the financial and physical constraints,the real seismic survey data are usually incomplete. Seismicdata reconstruction is a complex problem, and a large numberof researchers have devoted themselves to the research of thisfield. Consequently, many approaches have been proposed tohandle this problem. From the point of view of data organiza-tion, these methods can be divided into two categories.

The low dimensional based methods, such as transform-basedmethods which utilize the properties of the seismic trace in anauxiliary domain (Hennenfent et al., 2010). Liner predictiontheory use the predictability of the signal in the f-x or t-x do-main (Naghizadeh and Sacchi, 2007). And methods which ex-ploit the low-rank nature of seismic data embedded in Hankelmatrices (Oropeza and Sacchi, 2011).

Those low dimensional based methods usually ignores the spa-tial structure of the seismic traces. While the spatial struc-ture coherence is very important for the seismic data comple-tion, hence recent developments in high dimensional tensorcompletion approaches exploit various tensor decompositionmodel are widely used in seismic data reconstruction (Kreimeret al., 2013; Ely et al., 2015a). Those high-order tensor de-composition approaches have became a trend for seismic datacompletion, and the exist different definitions for tensor de-composition that lead to different tensor completion model,i.e. the higher-order singular value decomposition (HOSVD)(Kreimer and Sacchi, 2011), the tuker decomposition (Da Silvaand Herrmann, 2013), and tensor SVD (tSVD) decomposition(Ely et al., 2015b).

In this paper, we focus on a new seismic data reconstructionalgorithm which based on low-tubal-rank tensor decomposi-tion model possesses extremely high precision seismic datarecovery performance. Because of the high redundancy or co-herence between one seismic trace to the others (Ely et al.,2015a), we assume that the fulled sampled seismic volume haslow-tubal-rank property in the tSVD domain. Therefore, wecan solve the seismic tensor completion problem through analternating minimization algorithm for low-tubal-rank tensorcompletion (Tubal-Alt-Min) (Liu et al., 2016a,b). We haveevaluated the performance of this approach on both syntheticand field seismic data.

NOTATIONS

The data in seismic survey is a natural high-dimensional ten-sor, such as the 3D poststack seismic data which consists ofone time or frequency dimension and two spatial dimensionscorresponding to xline and inline directions.

Throughout the paper, we denote those 3D seismic tensor intime domain by uppercase calligraphic letter, T ∈ Rm×n×k,and denote the frequency domain 3D seismic tensor by T ∈Rm×n×k correspondingly. Uppercase letter A ∈ Rm×n denotesmatrix, and lowercase boldface letter x ∈ Rn denotes vector.Let [n] denotes the set 1,2, . . . ,n. In addition, we introducean important tensor operator t-product (Kilmer et al., 2013).

t-product. The tensor-product T = X ∗Y of X ∈ Rn1×n2×k

and Y ∈ Rn2×n3×k is a tensor of size n1× n2× k, T (i, j, :) =∑n2s=1X (i,s, :)∗Y(s, j, :), for i ∈ [n1] and j ∈ [n3].

PROBLEM SETUP

From what we have stated above, we know that seismic datacomprises many traces that provide a spatio-temporal sam-pling of the reflected wavefield. However, caused by variousfactors, such lost many important informations. Such as theexist of reservoir, residential or any other obstacle in the seis-mic data acquisition areas will lead to under-sampled seismicrecord. The missing traces will complicate certain data pro-cessing steps such as the prediction accuracy of undergroundreservoirs. Hence, the completion step in seismic data process-ing is of grate significance.

In this paper, we explored the relationship between low-tubal-rank and under-sampled rate firstly, and found that low-tubalproperty is positively correlated with the sampling rate. Figure1 shows the detail experiment result. Base on this work, we as-

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Figure 1: The empirical CDF of singular value.

Alg. 1 Tubal Alternating Minimization: AM(PΩ(T ), Ω, L, r)

Input: Observation set Ω ∈ [n]× [m]× [k] and the correspond-ing elements PΩ(T ) , number of iterations L, target tubal-rankr.

1: X0 ← Initialize(PΩ(T ),Ω,r),2: X0 ← fft(X0, [], 3), TΩ← fft(TΩ, [], 3),PΩ ← fft(PΩ, [], 3),

3: for l = 1 to L doYl ← LS Y( TΩ, PΩ, Xl−1, r ),Xl ← LS X( TΩ, PΩ, Yl , r),

4: end for5: X ← ifft( XL, [], 3); Y ← ifft( YL, [], 3),

Output: Pair of tensors ( X , Y ).

sume that the full sampled seismic data volume has low-tubal-rank property and under-sampled traces will increase the tubalrank. Therefore, the poststack 3D seismic data reconstruc-tion can be tackled with tensor completion tools that usingthe low tubal rank property. The statement above transformto mathematical representation is that T ∈ Rm×n×k is a 3Dseismic data with tubal-rank equal to r. Then, by observing aset Ω ⊂ Rm×n×k of T ’s elements, we get the under-sampledseismic data TΩ. Then, our aim is to recover T from TΩ. Thetensor reconstruction problem can be formulated as following

optimization function:

T = argminX∈Rm×n×k

rank(X ),

s.t. PΩ(X ) = PΩ(T ).(1)

Here,PΩ(·) denote the projection of a tensor onto the observedset Ω, TΩ = PΩ(T ). The Tubal-Alt-Min algorithm proposedby Liu recently, which can complete the low tubal rank ten-sor with very high currency in several iterations is a perfectapproach to solve this problem.

SOLUTION

In the Tubal-Alt-Min algorithm, the target 3D seismic volumeT ∈Rm×n×k can be decomposed as T =X ∗Y , X ∈Rm×r×k,Y ∈ Rr×n×k, and r is the target tubal-rank. With this decom-position, the problem (1) reduces to

T = argminX∈Rm×r×k ,Y∈Rr×n×k

‖PΩ(T )−PΩ(X ∗Y)‖2F . (2)

This cost function can be solved by the alternating minimiza-tion algorithm for low tubal rank tensor completion designedby Liu. The main algorithm steps are showing as Alg 1.

The key problem of Alg. 1 is the tensor least square mini-mization, which was solved by the providing methods in Liu’spaper. The main ideal is to decompose (2) into n separate stan-dard least squares minimization problem in the frequency do-main. Then, we just need to solve a least square problem likethe following form each step:

x = argminx∈Rrk×1

‖b−A1A2x‖2F . (3)

PERFORMANCE EVALUATION

To evaluate the performance of the algorithm we adopted, twocommonly used evaluation criteria in seismic data completionfiled have been used for comparison - the reconstruction errorand the convergence speed.

• Reconstruction error: here we adopted the relative squa-re error as a scale standard which defined as RSE =‖T −T ‖F/‖T ‖F .

• Convergence speed: we measure decreasing rate of theRSE across iterations by linearly fitting the measuredRSEs.

In order to have an intuitive performance comparison, we com-pared with two other seismic data volume completion algo-rithm. The Parallel matrix factorization algorithm (PMF) (Gaoet al., 2015) and the tensor singular value decomposition basedalgorithm, also called tensor nuclear norm algorithm (TNN)(Ely et al., 2015b) for seismic reconstruction. We applied thosealgorithm both on synthetic and real seismic data, the follow-ing subsections will demonstrate the detail performance com-parison.

Synthetic data exampleWe use a Ricker wavelet with central frequency of 40 Hz togenerate a simple 3D seismic model with two dipping planes.The seismic data corresponds to a spatial tensor of size 64×64× 256, 256 time samples with the time sampling rate of 1ms and 64 corresponding to inline and xline direction. Then,through tSVD decomposition we get U , S, and V . Accordingto the decomposition result, we choose the first 2 tubes of S,and make other tubes elements equate to zeros, form a newtensor S. Then we get the tensor T = U ∗ S ∗V which tubal-rank is 2.

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Figure 3: Convergence speed for the three algorithms on syn-thetic data.

Firstly, we apply Algorithm 1 to decompose the low-tuabl-ranktensor of our data set at different sampling rate vary from 5%to 95% and set the tubal-rank equate to 2. Using these decom-positions, we generate our reconstructed data and compare theerror between the low-tubal-rank reconstruction and full sam-pled data. Applying two other algorithm we stated above toreconstruct the data at the same condition. Because of all ofthe three algorithms include random sampling operator, weaveraged those algorithms’ performance under 20 above ex-periments. Figure 2 shows the relative square error (RSE) ofthe three algorithms. From these curves, we see that the per-formance of our algorithm is very outstanding. Even there areonly 30% sampling traces, it can also get a relative perfect re-construction data. As the increase of sampling rate, the recon-struction error of Tubal-Alt-Min algorithm decrease rapidly.Comparing with TNN, when the sampling rate over 50%, itimproves the recovery error by orders of magnitude. It’s re-covery error also better than the other algorithm almost in thewhole sampling rate range.

Secondly, to evaluate the reconstruction error, we fixed the sa-

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Figure 4: (a) Full sampled synthetic data. (b) Under-sampledmeasured data for the case when 40% of the traces in (a) wasremoved. (c) The recovered traces of (b), it’s RSE< 1e−4. (d)The relative residual between (c) and (a), when sampling rateequal to 40%, there almost no residual between original dataand reconstruction data.

mpling rate to be 40% and set the RSE tolerance of the three al-gorithms equal to 1e-4. Then evaluate relative square error andconvergence speed for the three algorithms. Figure 3 showsthat Tubal-Alt-Min convergence at 9th iteration, TNN-ADMMterminates at the 60-th iteration, PMF used 77-th iterations toreach the preset threshold. The convergence speed of our al-gorithm is obviously better than other algorithms.

Then, we fixed the sampling rate at 40% to evaluate the com-pletion performance on seismic data. The portion of reconstruc-tion result shows in figure 4. From figure 4 (b), 4 (c) and 4 (d),we observe that the missing traces are effectively recovered.

Filed data exampleWe also test the performance of the reconstruction method ona land data set that was acquired to monitor a heavy oil fieldin Anyue mountain, China. Our test data is a 25× 200× 600tensor cut from the full-sampled area of the filed data. On thisbasis, we randomly sample 50% traces in the seismic tensor,then reconstruct it. To reconstruct the traces, we evaluated thelow-tubal-rank of the data manually. Determined by the tSVD,we found it’s first 16 eigentubes’s l2 norm is much larger thanthe rest in almost 40 times. Consequently, we set the parameterof Alg. 1 r = 16. Figure 4 shows portion of the result cut alonginline direction. From the comparison of figure 5 (a), 5 (c) and

Page 4: arXiv:1704.02445v1 [cs.CE] 8 Apr 2017kP W(T) P W(XY)k2F: (2) This cost function can be solved by the alternating minimiza-tion algorithm for low tubal rank tensor completion designed

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Figure 6: The reconstruction result of filed data. (a) Thehorizontal-slice of filed data from Anyue survey areas. (b)Randomly sampled 40% trances from (a). (c) The data recov-ered by Tubal-Alt-Min algorithm, it’s RSE reached 1e-7. (d)The data recovered by TNN whose RSE converged to 1e-3.

5 (d), the reconstruction performance is such amazing that al-most no residual between 5 (a) and 5 (c) Compared with thereconstruction result of TNN, it seems no difference. However,the RSE gap between them almost have a few orders of magni-tude. Figure 5 shows the difference between the specific detailsof the seismic data traces restored by the two algorithms.

CONCLUSION

In this article, we formulate the problem of poststack seismicdata reconstruction as an low-tubal-rank decomposition prob-lem. The adopted method is based on the alternating mini-mization approach for low-tubal rank tensor completion. Theunknown low-tubal-rank tensor is parameterized as the prod-uct of two much smaller tensors with the low-tubal-rank prop-erty being automatically incorporated, and Tubal-Alt-Min al-ternates between estimating those two tensors using tensor leastsquares minimization. The biggest advantage of our algorithm

is that it can achieve very high recovery accuracy in several it-

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Figure 7: The reconstruction traces of filed data. (a) Thelateral-slices of filed data from Anyue survey areas. (b) Tracesrecovered by TNN. (c) Traces recovered by our algorithm.From the recovered traces in the blue rectangles, our algorithmhas an obvious performance advantages, which can recovermore details of the seismic traces.

erations. From the experimental result, it potently proved thatcompared with contrast algorithms our algorithm improves therecovery error by orders of magnitude with much better con-vergence speed for higher sampling rates.

ACKNOWLEDGMENTS

We would like to acknowledge financial support from the Na-tional Natural Science Foundation of China (Grant No.U1562218).

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Da Silva, C., and F. Herrmann, 2013, Hierarchical tucker tensor optimization-applications to 4d seismic data interpolation: Pre-sented at the 75th EAGE Conference & Exhibition incorporating SPE EUROPEC 2013.

Ely, G., S. Aeron, N. Hao, and M. E. Kilmer, 2015a, 5d and 4d pre-stack seismic data completion using tensor nuclear norm (tnn),in SEG Technical Program Expanded Abstracts 2013: Society of Exploration Geophysicists, 3639–3644.

Ely, G. T., S. Aeron, N. Hao, and M. E. Kilmer, 2015b, 5d seismic data completion and denoising using a novel class of tensordecompositions: Geophysics, 80, V83–V95.

Gao, J., A. Stanton, and M. D. Sacchi, 2015, Parallel matrix factorization algorithm and its application to 5d seismic reconstructionand denoising: Geophysics, 80, V173–V187.

Hennenfent, G., L. Fenelon, and F. J. Herrmann, 2010, Nonequispaced curvelet transform for seismic data reconstruction: Asparsity-promoting approach: Geophysics, 75, WB203–WB210.

Kilmer, M. E., K. Braman, N. Hao, and R. C. Hoover, 2013, Third-order tensors as operators on matrices: A theoretical andcomputational framework with applications in imaging: SIAM Journal on Matrix Analysis and Applications, 34, 148–172.

Kreimer, N., and M. D. Sacchi, 2011, A tensor higher-order singular value decomposition (hosvd) for pre-stack simultaneousnoise-reduction and interpolation: Seg Technical Program Expanded Abstracts, 3069–3074.

Kreimer, N., A. Stanton, and M. D. Sacchi, 2013, Tensor completion based on nuclear norm minimization for 5d seismic datareconstruction: Geophysics, 78, V273–V284.

Liu, X.-Y., S. Aeron, V. Aggarwal, and X. Wang, 2016a, Low-tubal-rank tensor completion using alternating minimization: SPIEDefense+ Security, International Society for Optics and Photonics, 984809–984809.

——–, 2016b, Low-tubal-rank tensor completion using alternating minimization: 9848, 984809.Naghizadeh, M., and M. D. Sacchi, 2007, Multistep autoregressive reconstruction of seismic records: Geophysics, 72, V111–V118.Oropeza, V., and M. Sacchi, 2011, Simultaneous seismic data denoising and reconstruction via multichannel singular spectrum

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