Hawaiian Volcano Update: Kīlauea Intrusion Ongoing, Maunaloa Anniversary, December 1, 2023

Kīlauea's intrusion continues, affecting the summit region, Southwest Rift, and the Upper East Rift through ongoing earthquakes and ground deformation. Monitoring signals show a similar progression since the start of October, sometimes inflating more within the summit caldera, and sometimes inflating more in the area to the south and west towards the Southwest Rift.

Events in the Upper East Rift increased in prominence during the past 2 weeks, prompting Hawaiʻi Volcanoes National Park to close the Chain of Craters Road for a single day on November 21st. However, as with the pattern elsewhere across the intrusion, waxing and waning of effects have been common as the magma supply pulses, and have slowed over the past week. The volcano remains primed with the potential to erupt, but is still able to compensate for the increased pressure through its underground injections across a wide area, at least for now. O

verall, 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 celebrates the 1-year anniversary of its 2022 eruption, still continuing to recharge after the 12-day outburst. Earthquakes deep and shallow have slowed under Maunaloa, which may have felt the effects of ground movement in the Southwest Rift of Kīlauea, its neighbor to the south. The occurrence of recent shallower seismicity may otherwise signal a change in the volcano's dynamics over the coming months, yet for now, the volcano remains at the lowest USGS warning level.

As usual we review the monitoring signals, imagery and reports available courtesy of the USGS Hawaiian Volcano Observatory, annotating the presentation on screen and discussing live viewer questions as we go.