Kīlauea Weekly Report: June 8, 2021

Kīlauea remains quiet, with only minor settling of its hardened lava lake surface in the past week. There is still the usual magmatic movement underground, though, causing slight increases in seismicity and ground tilt as the volcano builds towards reactivation or its next eruption. The distinction in terminology only serves to indicate whether lava emerges within 90 days of its previous surface activity, since that is the current consensus definition of an eruptive pause. Regardless of the short-term quiescence or pause and the lack of visible lava, the volcano remains under scrutiny as it continues a longer-term trend of heightened activity. This week’s USGS-HVO update notes, “No surface activity or evidence of recent surface activity has been observed over the past week, except for minor subsidence on the order of 1-2 meters (3-7 feet). Small, warmer-temperature spots around the rim and in local cavities remain visible in thermal webcam imagery, although at temperatures well below those associated with molten lava.” Perhaps consistent with this, the most interesting signal on the monitors this week appears to be a 3 m (10 ft) elevation drop shown in the plot of lake depth on June 6. A review of thermal images only shows a localized, subtle change suggesting a very small, one-time collapse specific to the measured location. Gas emissions remain low as they have over the past two weeks, with ~50 t/d of SO2 reported on June 4. The settling of the crusts of hardened lava lakes is an expected part of the post-eruption process, documented in several historical eruptions. The biggest changes often happen soonest after the eruption, while gas is still easily released to create underground space to drive small-scale collapses. Even after the lava hardens, it continues to contract as it cools, leading to widening cracks that can also create void space and cause surface subsidence. Repeat visitors to Hawaiʻi Volcanoes National Park may have noticed this at Kīlauea Iki, where cracks on the hardened lava lake surface are still slowly opening due to cooling and contraction, over 61 years since the end of its eruption. Join our weekly live video review of Kīlauea and Maunaloa volcanoes, at 5pm Hawaiʻi time Thursdays as of June 2021! To support our productions please like, share and subscribe! Mahalo! #Kilauea2021