Change search
ReferencesLink to record
Permanent link

Direct link
Robust estimation of seismic coda shape
University of Helsinki, Finland .
Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Institute Dynam Geospheres, Russia .
2014 (English)In: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 197, no 1, 557-565 p.Article in journal (Refereed) Published
Abstract [en]

We present a new method for estimation of seismic coda shape. It falls into the same class of methods as non-parametric shape reconstruction with the use of neural network techniques where data are split into a training and validation data sets. We particularly pursue the well-known problem of image reconstruction formulated in this case as shape isolation in the presence of a broadly defined noise. This combined approach is enabled by the intrinsic feature of seismogram which can be divided objectively into a pre-signal seismic noise with lack of the target shape, and the remainder that contains scattered waveforms compounding the coda shape. In short, we separately apply shape restoration procedure to pre-signal seismic noise and the event record, which provides successful delineation of the coda shape in the form of a smooth almost non-oscillating function of time. The new algorithm uses a recently developed generalization of classical computational-geometry tool of alpha-shape. The generalization essentially yields robust shape estimation by ignoring locally a number of points treated as extreme values, noise or non-relevant data. Our algorithm is conceptually simple and enables the desired or pre-determined level of shape detail, constrainable by an arbitrary data fit criteria. The proposed tool for coda shape delineation provides an alternative to moving averaging and/or other smoothing techniques frequently used for this purpose. The new algorithm is illustrated with an application to the problem of estimating the coda duration after a local event. The obtained relation coefficient between coda duration and epicentral distance is consistent with the earlier findings in the region of interest.

Place, publisher, year, edition, pages
Oxford University Press (OUP): Policy P - Oxford Open Option A , 2014. Vol. 197, no 1, 557-565 p.
Keyword [en]
Time-series analysis; Image processing; Body waves
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:liu:diva-106681DOI: 10.1093/gji/ggu002ISI: 000334096600036OAI: oai:DiVA.org:liu-106681DiVA: diva2:718432
Available from: 2014-05-21 Created: 2014-05-19 Last updated: 2014-05-21

Open Access in DiVA

fulltext(1464 kB)123 downloads
File information
File name FULLTEXT01.pdfFile size 1464 kBChecksum SHA-512
529fc4efcf613409c20f2f38eba31233975ea960c8a8017aa977d543986a574fb10e45e5efaebe6fb4a77a169fcb73137672abf92b2b9efef571e1844dd1732d
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Polishchuk, Valentin
By organisation
Communications and Transport SystemsThe Institute of Technology
In the same journal
Geophysical Journal International
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 123 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 48 hits
ReferencesLink to record
Permanent link

Direct link