Earthquake Analysis Suggests Dyke Intrusion in 2019 Near Tarawera Volcano, New Zealand

Tarawera volcano (New Zealand) is volumetrically dominated by rhyolitic lavas and pyroclastic deposits, but the most recent event in AD 1886 was a basaltic Plinian fissure eruption. In March 2019 swarm of at least 64 earthquakes occurred to NE volcano, as recorded New Zealand Geohazard Monitoring Network (GeoNet). We use seismological analysis show that this likely caused dyke intruded into brittle crust between depths 8–10 km propagated toward for 2 rate 0.3–0.6 m s −1 . infer composition stress-guided topographic load volcanic edifice. Dyke intrusions nature are common occurrence similar process may have during eruption with sourced from some lateral distance away volcano. The intrusion not detected InSAR geodesy we synthetic models geodetic monitoring could only detect ≥6 wide these depths. Improvements monitoring, combined detailed analysis, better future magmatic region serve help assess ongoing changes system associated possibilities event.