← Back to Sessions

Using Empirical Source Templates as Mother Wavelets in the Continuous Wavelet Transform

Session: Explosion Seismology Applications and Advances I

Type: Oral

Date: 4/19/2021

Presentation Time: 10:00 AM Pacific

Description: 

A mother wavelet can be constructed from a template derived from observations of a seismic event. Using the entire signal of a template event as a wavelet within the continuous wavelet transform produces the ultimate sparse representation of repeating events since, in principle, the detected event can be represented by a single wavelet coefficient in the scale-time domain. Use of empirical wavelets generalizes template correlation since the time scaling of the empirical wavelet mimics changes in relative arrival times between phases. A template derived from an event at one seismic station might be appropriate for a close by station or for other events of similar mechanism close to the template event. This hypothesis is tested using local explosion data recorded by the 2016 IRIS Wavefields Community Experiment. Use of an empirical wavelet derived from the 2000lb shot approximately 35km from the IRIS experiment clearly detects the same explosion from noisy data at other stations in the array and for the 500lb explosion at the same shotpoint. The two 250lb explosions were not detected because of relatively higher levels of background noise. These results suggest the additional possibility of reconstructing waveforms from small events using a template event as the mother wavelet.

Presenting Author: Charles A. Langston

Student Presenter: No

Authors