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Automatic picking of seismic arrivals in local earthquake data using an artificial neural network
308A
GEOLOGY:EARTHQUAKES
environmental changes. A program for investigating recognizable variations in soil-gas radon content associated with earthquake activity, is being carried out by the Radiation Protection and Safety Centre in Algeria. A network of radon measuring stations has been implanted along seismic faults in northern Algeria. A 4 year span of monthly readings of radon concentrations using solid state nuclear track detectors has been collected. The field results obtained in terms of temporal variations of radon concentrations have been compared with the meteorological and seismic data of the region. (Authors)
957039 A multi-objective seeond-order optimal design for deforming networks Peiliang Xu & E. Grafarend, Geophysical Journal International, 120(3), 1995, pp 577-589. Geodetic control networks, have been set up in seismically active areas to monitor regional crustal movements. Measured data can be used to infer some important engineering parameters like normal strain and shear. The success of applications of geodetic methods in prediction of earthquakes, however, depends to an appreciable extent on the reproducibility of a sequence of events. Two indicators of reproducibility are slip- and strain-predictable. This study investigates optimal design problems of deforming networks from the viewpoint of multi-objective optimal theory. Based on accuracy, reliability and the character of a deformation model, a multi-objective optimal technique has been developed for designing a 3-D deforming network. It simultaneously takes into account optimal designs of displacement vectors and principal strain components. A criterion matrix for the principal components of strain is constructed. Numerical results are discussed in terms of objective function values, error ellipsoids of displacement vectors and principal components of strain. (from Authors)
957040 Stochastic modeling of seismic surface rotations A. Castellani & Z. Zembaty, Natural Hazards, 10(1-2), 1994, pp 181-191.
957042 Automatic picking of seismic arrivals in local earthquake data using an artificial neural network Hengchang Dal & C. Macbeth, Geophysical Journal International, 120(3), 1995, pp 758-774. A preliminary study is performed to test the ability of an artificial neural network (ANN) to detect and pick seismic arrivals from local earthquake data. This is achieved using three-component m~ordings by utilizing the vector modulus of these seismic records as the network input. 877 protriggered recordings from two stations in a local earthquake network are analysed by an ANN trained with only nine P waves and nine noise segments. Comparing the results with manual picks, the ANN can accurately detect 93.9% of the P waves and also 90.3% of the S waves. The ANN has potential as a tool to pick arrivals automatically. This algorithm has been adopted as a component in the early stages of the development of an automated subsystem to analyse local earthquake data. (from Authors) 957043 Assessment of environmental quality for earthquake risk in Beijing area - the application of geographic information system (GIS) Han Xhujun, Jiang Pu, Wang Liangmou, Yu Ketao & Liu Peixun, Seismology & Geology, 16(3), 1994, pp 211-215. Preliminary work in applying GIS to research on earthquake risk is presented. The earthquake risk environment in the Beijing area consists of three sub-environments, the seismological, the geological and the exposed sub-environment. The relation between earthquake risk and affecting factors is qualitatively or partly quantitatively discussed. Based on the comprehensive analysis of all kinds of factors, supported by GIS, derision and assessment of the earthquake risk environment in the Beijing area is made. (from Authors) 957044 Features of geonomic prognostic functions for the maximnm possible earthquake V. Schenk, Z. Schenkova & V. G. Girls, Natural Hazards, 10(1-2), 1994, pp 97-115.
In this paper, a stochastic analysis of surface rotations during earthquakes is presented. The surface motion is modelled by a spacetime random field. A method to obtain rotation based on direct differentiation of the random field is proposed with a reference to a second method based on wave decomposition. The advantages and disadvantages of both methods arc discussed in detail. (from Authors)
Artificial intelligence techniques are commonly applied to solving problems in which multidimensional statistical analyses of various quantities and their modelling prognostic functions can be used. This paper attempts to summarize the characteristics of the prognostic functions applied in the determination of the maximum possible earthquake. Geonomic quantities are reviewed and categorized with respect to their influence upon the estimation of the maximum possible earthquake. (Authors)
957041 Automated classification of local earthquake data in the BUG small array M. Joswig, Geophysical Journal International, 120(2), 1995, pp 262-286.
957045 Identification of a geological region for earthquakes using syntactic pattern recognition of seismograms M. Zhizhin, A. Gvishiani, D. Rouland, J. Bonnin & B. Mohammadioun, Natural Hazards, 10(1-2), 1994, pp 139147.
The Bochum University Germany (BUG) stations monitor the mining-induced seismicity in the Ruhr basin of NW Germany.Four of the stations form an array of small aperture. Automated classification of local earthquakes into different source regions and recognition of noise bursts can be described by a two-step approach; the recognition of sonogram patterns at each tingle station and the subsequent, rule-based coincidence evaluation. Both stages of the automated classification scheme were tested on routine observatory data of a one month period. The majority of earthquakes were reco~miTed at all sites, the identification of quarry blasts was excellent and most site-specific noise bursts were rejected. (from Author)
A relational database has been developed which permits the storage and retrieval of waveforms, together with essential parameters of events. The capability of the method is tested by applying it to broad-band records from the Geoscope Noumea station (New Caledonia). (Authors) 957046
A different intensity recording for reducing the uncertainty in its assessment: an application to the completeness analysis of earthquake catalogues R. Rotondi, F. Meroni & G. Zonno, Natural Hazards, 10(12), 1994, pp 47-58.
GEOLOGY:EARTHQUAKES
environmental changes. A program for investigating recognizable variations in soil-gas radon content associated with earthquake activity, is being carried out by the Radiation Protection and Safety Centre in Algeria. A network of radon measuring stations has been implanted along seismic faults in northern Algeria. A 4 year span of monthly readings of radon concentrations using solid state nuclear track detectors has been collected. The field results obtained in terms of temporal variations of radon concentrations have been compared with the meteorological and seismic data of the region. (Authors)
957039 A multi-objective seeond-order optimal design for deforming networks Peiliang Xu & E. Grafarend, Geophysical Journal International, 120(3), 1995, pp 577-589. Geodetic control networks, have been set up in seismically active areas to monitor regional crustal movements. Measured data can be used to infer some important engineering parameters like normal strain and shear. The success of applications of geodetic methods in prediction of earthquakes, however, depends to an appreciable extent on the reproducibility of a sequence of events. Two indicators of reproducibility are slip- and strain-predictable. This study investigates optimal design problems of deforming networks from the viewpoint of multi-objective optimal theory. Based on accuracy, reliability and the character of a deformation model, a multi-objective optimal technique has been developed for designing a 3-D deforming network. It simultaneously takes into account optimal designs of displacement vectors and principal strain components. A criterion matrix for the principal components of strain is constructed. Numerical results are discussed in terms of objective function values, error ellipsoids of displacement vectors and principal components of strain. (from Authors)
957040 Stochastic modeling of seismic surface rotations A. Castellani & Z. Zembaty, Natural Hazards, 10(1-2), 1994, pp 181-191.
957042 Automatic picking of seismic arrivals in local earthquake data using an artificial neural network Hengchang Dal & C. Macbeth, Geophysical Journal International, 120(3), 1995, pp 758-774. A preliminary study is performed to test the ability of an artificial neural network (ANN) to detect and pick seismic arrivals from local earthquake data. This is achieved using three-component m~ordings by utilizing the vector modulus of these seismic records as the network input. 877 protriggered recordings from two stations in a local earthquake network are analysed by an ANN trained with only nine P waves and nine noise segments. Comparing the results with manual picks, the ANN can accurately detect 93.9% of the P waves and also 90.3% of the S waves. The ANN has potential as a tool to pick arrivals automatically. This algorithm has been adopted as a component in the early stages of the development of an automated subsystem to analyse local earthquake data. (from Authors) 957043 Assessment of environmental quality for earthquake risk in Beijing area - the application of geographic information system (GIS) Han Xhujun, Jiang Pu, Wang Liangmou, Yu Ketao & Liu Peixun, Seismology & Geology, 16(3), 1994, pp 211-215. Preliminary work in applying GIS to research on earthquake risk is presented. The earthquake risk environment in the Beijing area consists of three sub-environments, the seismological, the geological and the exposed sub-environment. The relation between earthquake risk and affecting factors is qualitatively or partly quantitatively discussed. Based on the comprehensive analysis of all kinds of factors, supported by GIS, derision and assessment of the earthquake risk environment in the Beijing area is made. (from Authors) 957044 Features of geonomic prognostic functions for the maximnm possible earthquake V. Schenk, Z. Schenkova & V. G. Girls, Natural Hazards, 10(1-2), 1994, pp 97-115.
In this paper, a stochastic analysis of surface rotations during earthquakes is presented. The surface motion is modelled by a spacetime random field. A method to obtain rotation based on direct differentiation of the random field is proposed with a reference to a second method based on wave decomposition. The advantages and disadvantages of both methods arc discussed in detail. (from Authors)
Artificial intelligence techniques are commonly applied to solving problems in which multidimensional statistical analyses of various quantities and their modelling prognostic functions can be used. This paper attempts to summarize the characteristics of the prognostic functions applied in the determination of the maximum possible earthquake. Geonomic quantities are reviewed and categorized with respect to their influence upon the estimation of the maximum possible earthquake. (Authors)
957041 Automated classification of local earthquake data in the BUG small array M. Joswig, Geophysical Journal International, 120(2), 1995, pp 262-286.
957045 Identification of a geological region for earthquakes using syntactic pattern recognition of seismograms M. Zhizhin, A. Gvishiani, D. Rouland, J. Bonnin & B. Mohammadioun, Natural Hazards, 10(1-2), 1994, pp 139147.
The Bochum University Germany (BUG) stations monitor the mining-induced seismicity in the Ruhr basin of NW Germany.Four of the stations form an array of small aperture. Automated classification of local earthquakes into different source regions and recognition of noise bursts can be described by a two-step approach; the recognition of sonogram patterns at each tingle station and the subsequent, rule-based coincidence evaluation. Both stages of the automated classification scheme were tested on routine observatory data of a one month period. The majority of earthquakes were reco~miTed at all sites, the identification of quarry blasts was excellent and most site-specific noise bursts were rejected. (from Author)
A relational database has been developed which permits the storage and retrieval of waveforms, together with essential parameters of events. The capability of the method is tested by applying it to broad-band records from the Geoscope Noumea station (New Caledonia). (Authors) 957046
A different intensity recording for reducing the uncertainty in its assessment: an application to the completeness analysis of earthquake catalogues R. Rotondi, F. Meroni & G. Zonno, Natural Hazards, 10(12), 1994, pp 47-58.