Six tests of sparse log decon

نویسندگان

  • Antoine Guitton
  • Jon Claerbout
چکیده

Previously, we developed a sparseness-goaled decon method. Here we test it on six data sets. None showed the unfortunate phase-shift we always see with minimum-phase decon. None showed the polarity reversals or time shifts that perplexed our earlier work. Results on all six data sets enhance polarity visibility. We had expected to see sparseness decon limit the bandwidth in some natural way unlike prediction-error decon with its white output. Instead, in all the cases our sparseness decon boosted frequencies much the way predictive decon does. We had not expected to see an estimated shot waveform containing a lot of low-frequency sea surface waves. One such result provoked a new theoretical development not yet tested (Claerbout and Guitton, 2012). INTRODUCTION We have tested our basic sparse deconvolution method on six data sets. Results are generally positive, but not totally as expected. We are pleased to report none of the results here showed the kind of phase-shift issues we always see with minimum-phase decon. For the most part, the decons enhance the appearance of polarity. One of the data sets (DATA4) had a clearly defective gun array with an extremely non-minimum phase wavelet and our deconvolution worked wonders on it (see Figure 5). One problem persisted until about six months ago: we could not be sure which of the three lobes of the Ricker wavelet would be enhanced. Then a new regularization, proposed theoretically, ensured spiking on the central Ricker lobe, meaning we shall no longer see apparent polarity reversals or time shifts. We had expected to see that sparseness would limit the bandwidth in some natural way. Instead, in all the cases the sparseness decon boosted frequencies much the same way predictive decon does. Worse yet, one of the shot waveforms contained a lot of low-frequency sea surface waves. Serendipitously this bad result provoked Jon Claerbout to introduce theory augmentations (Claerbout and Guitton, 2012) that have not yet been coded or tested. REGULARIZATIONS Because predictive decon fails on the Ricker wavelet, Zhang and Claerbout (2010) devised an extension to non-minimum phase wavelets. Then Claerbout et al. (2011)

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Six tests of sparse log decon

Previously we developed a sparseness-goaled decon method. Here we test it on six data sets. None showed the unfortunate phase-shift we always see with minimumphase decon. None showed polarity reversals or time shifts that perplexed our earlier work. Results on all six data sets enhance polarity visibility. We had expected to see sparseness decon limit the bandwidth in some natural way unlike pr...

متن کامل

Decon in the log domain with variable gain

Because predictive decon fails on the Ricker wavelet, earlier we devised an extension to non-minimum phase wavelets (Yang et al, 2011). It showed remarkable clarity of seismogram polarity. Here we improve our method by a log spectral parameterization. Another innovation here is correctly handling time-variable gain. Since filtering does not commute with TV gain, gain is now done after decon (no...

متن کامل

Accurate clinical detection of exon copy number variants in a targeted NGS panel using DECoN

Background: Targeted next generation sequencing (NGS) panels are increasingly being used in clinical genomics to increase capacity, throughput and affordability of gene testing. Identifying whole exon deletions or duplications (termed exon copy number variants, 'exon CNVs') in exon-targeted NGS panels has proved challenging, particularly for single exon CNVs.  Methods: We developed a tool for t...

متن کامل

Polarity preserving decon in “N log N” time

A slight modification to Fourier spectral factorization enables deconvolution to preserve and enhance seismogram polarities. It spikes the center lobe of the Ricker wavelet. It works by tapering at small lags the antisymmetric part of the time-domain representation of the log spectrum.

متن کامل

Decon nement, Color Screening and Quarkonium Suppression

The study of color decon nement in strongly interacting matter leads to challenging problems of theoretical as well as of more phenomenological nature. How does the transition from hadronic matter to a quark-gluon plasma take place is it a genuine phase transition or some less `singular' cross-over, and what are the basic properties of the new decon ned medium? In the chiral limit (mq = 0) and ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2012