35 Recent advances in our understanding of the New Madrid seismic zone
Thorough understanding of the New Madrid seismic zone will require integration of observations relating to surface features, the crust and the upper mantle. All contributions are welcomed.
Wednesday, 11 March 2026
8:30 AM - 12:00 PM
RCC, 104
What Are Waveform Cross Correlations Telling Us About Earthquakes? A View From South Carolina
Paper number: 35-4
Program: Technical Sessions
Time: 9:30 AM – 9:45 AM
Authors
Abstract
Waveform template matching, using the waveform of a known earthquake to search for previously unknown earthquakes, has become a popular method to improve earthquake detection. This method yields a cross correlation coefficient, which quantifies the degree of similarity between one waveform and another, with a sufficiently high correlation usually considered a “detection” of a previously unknown event. Here I will examine cross correlation coefficients between events within 3 earthquake sources in South Carolina: a) induced seismicity at Monticello Reservoir, b) a natural earthquake swarm near Elgin, South Carolina and c) background seismicity in the source zone of the 1886 M 7 earthquake near Summerville, South Carolina. I will examine how differences in source parameters (magnitude, focal mechanism), location and background noise impact cross correlation coefficients. Results to date suggest that waveforms of larger events do not correlate well with smaller events located nearby; this is potentially an impact of source-time function differences and/or site response at the recording station. In addition the low signal-to-noise ratio of the smallest magnitude events detected generally precludes a high cross correlation coefficient, even if two events are located close to each other and are of similar magnitude.
Geological Society of America Abstracts with Programs. Vol. 58, No. 1
doi: 10.1130/abs/2026SE-411719
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