Based on observations during helicopter overflights, visual observations from HVO and National Park Service (NPS) crews, and web camera views, HVO reported that during 16-22 April lava flowed SE through a lava tube system underneath Kilauea’s Thanksgiving Eve Breakout (TEB) and rootless shield complex to the Waikupanaha ocean entries. The Ki ocean entry was inactive during 19-22 April. Occasionally, incandescence from breakouts along the lava-tube system was noted.
During the reporting period, Kilauea summit earthquakes were located beneath Halema’uma’u Crater, beneath Napau Crater, along the S-flank faults, and along the upper E and SW rift zones. The eruption from the vent in Halema’uma’u Crater continued to produce white ash plumes that drifted mainly SW. During most nights incandescence was seen at the base of the plume. On 16 April, a small explosion from the vent ejected ash onto the overlook parking lot and on a portion of Crater Rim drive. Seismic tremor was elevated.
Sulfur dioxide emission rates from the summit area have been elevated at 2-4 times background values since early January. The emission rate fluctuated between 870 and 1150 tonnes per day during 15-21 April, compared to a background rate of 150-200 tonnes per day.
Sources: US Geological Survey Hawaiian Volcano Observatory (HVO), Washington Volcanic Ash Advisory Center (VAAC) – “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”