Hawaiian Volcano Update: Kīlauea Intrusion Cycle Repeats

Last month's intrusion cycle south of Kīlauea caldera and extending into the Southwest Rift consisted of several pulses of magma injection over three weeks, before slowing down for a full week. On November 10th, another intrusion cycle began following inflation at Halemaʻumaʻu, presumably due to another slug of magma reaching the volcano's shallow reservoir system. Following last month's activity, the magma pathways to the southwest appear to still be open and responding to the pressure cycles within the caldera.

Overall, the situation remains much the same as in recent weeks, with extended underground adjustments at one end of the spectrum of possibility, and a short lead-up to an eruption at the other end. All changes are contained within Hawaiʻi Volcanoes National Park, and pose no increased threat to people at this time.

Gas emissions remain at background levels for the volcano around 100 tonnes of SO2 per day, but can still affect sensitive individuals in downwind areas. Typically gas emissions are at their worst at the start of each eruption, thus between eruptions is the best time for those exposed to prepare.

Maunaloa's seismicity drastically decreased this week particularly in the deep zones under the mountain, following a shallower swarm below sea level two weeks ago and a slowdown last week. Approaching the one-year anniversary of its 2022 eruption, our largest volcano continues passively filling with magma, as evidenced by GPS and ground-tilt signals. While the occurrence of recent shallower seismicity may signal a change in the coming months, for now the volcano remains at the lowest USGS warning level.