LAUSR

The intense volcanic and seismic activity at Kilauea volcano, Hawaii in 2018 provides an opportunity to understand the characteristics and driving forces of volcano earthquake clusters. Nearest neighbor distance analysis of a high‐resolution earthquake catalog reveals two modes of clustering: M1 and M2. M1 clusters focus on events within short space and time windows, and are concentrated within isolated fault patches. Examination of three structures shows a gradual increase of source radius (assuming a constant stress drop) and spatial migration of seismicity, likely representing aseismic growth of peripheral faults. M2 clusters focus on temporal clustering of all seismicity within the caldera and most clusters represent complete seismicity cycles between major collapse events. Beginning in late June, the M2 cluster duration gradually increased. The event numbers show a strong linear relationship with the tilt rates on the transverse component, suggesting earthquake rates are controlled by the deformation rate within the caldera.