EPISODES Platform Documentation

Application User Guides > Source and Shaking Parameters Estimation

P Wave Detection Tool user guide ​

TIP

This document contains instructions for running application P and S Waves Detection Tool within the EPISODES Platform. The application is a tool for automatic detection of the first arrival time of the P waves. The detection is carried out in a time window of 4 seconds. It uses Deep Learning technique based on a convolutional neural network to process the seismograms and detect the first arrival times. The algorithm finds the arrival times with the mean difference from the human-created picks of -0.003 s with the standard deviation of 0.023 s. The model is based on Ross, Meier and Hauksson (2018).
To obtain more general information about working with applications within the Platform, see Applications Quick Start Guide.

NOTE

CATEGORY Source and Shaking Parameters Estimation

KEYWORDS Waveform viewing, Picking on waveform

CITATION If you use the results or visualizations retrieved from this application in a publication, then you must cite the data source as follows:

Ross, Z. E., Meier, M.-A., & Hauksson, E. (2018). P wave arrival picking and first-motion polarity determination with deep learning. Journal of Geophysical Research: Solid Earth, 123, 5120– 5129. doi: 10.1029/2017JB015251.

Orlecka-Sikora, B., Lasocki, S., Kocot, J. et al. (2020) An open data infrastructure for the study of anthropogenic hazards linked to georesource exploitation., Sci Data 7, 89, doi: 10.1038/s41597-020-0429-3.

Input file specification ​

The application requires a SAC Waveform (or any subtype) containing seismogram on which the wave arrival time should be detected.

Figure 1. Application input files specification.
Figure 1. Application input files specification.

Filling form values ​

The application form has only one value to be filled - the center of the time window in which the algorithm should look for the wave arrival (marked in Figure 2). This might be either filled by hand or chosen from the input seismogram visualisation (by clicking on the plot) - the chosen window center is marked with black dashed line and the area in which the algorithm will be able to find the wave arrival is marked with a light grey background.

Note, that the center of the window will look similar to the pick signifying the wave arrival (see the next section and Figure 3), but the latter has a more exact location within the grey area from Figure 2.

Figure 2. Application form with values filled.
Figure 2. Application form with values filled.

Produced output ​

The output of the application is a time value marking the wave detection (marked in Figure 3). The time is also displayed as a pick on the original input file.

Figure 3. Application output - SAC waveform with resulting P wave pick displayed.
Figure 3. Application output - SAC waveform with resulting P wave pick displayed.