Comprehensive Processing Workflow for Seismic Nodal Array Data: Application to the North Peace River Earthquake Sequence, Northwestern Alberta

Seismic nodal arrays are increasingly used in local-scale seismic studies, offering a rapid, cost-effective deployment, and providing high-resolution event locations that can enhance understanding of seismic clusters. This report outlines a comprehensive processing workflow for seismic nodal array data, including preprocessing, event detection, phase picking, event location, magnitude estimation, catalogue building, and source mechanism analysis. Each step is described in detail and illustrated through a case study using three rounds of seismic nodal array data collected in the area north of the town of Peace River.

The results show that with just three months of deployment, the nodal array detected 340 events in the Peace River region, with the largest event in the catalogue having a local magnitude of 2.83. Among these, 29 events had local magnitudes greater than or equal to 1, and 13 of these events were not detected by the regional seismic array. Despite the limited spatial coverage with only seven seismic nodes, the event locations show a good agreement with those recorded by the regional array. Most events occurred at depths between 4 and 6 km below the ground surface. Notably, the nodal array detected a small seismic cluster of 26 events within a 15 km radius of disposal wells that was not previously detected by the regional array. The North Peace River earthquake sequence is currently under assessment, and it is believed that the high-resolution catalogue from the nodal array data can help elucidate the potential induced seismic origin of this sequence.