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HVO scientists—equipped with specialized safety gear—continue the Kīlauea caldera volcanic gas mapping within the closed area of Hawai‘i Volcanoes National Park with NPS permission.
HVO scientists collect detailed data to assess hazards and understand evolving processes at Kīlauea's summit, all of which are shared with the National Park Service and emergency managers. Access to this hazardous area is by permission from, and in coordination with, Hawai‘i Volcanoes National Park.
HVO scientists continue their survey of Kīlauea caldera floor, including the down-dropped block, for diffuse volcanic gas emissions. This photo shows a large crack, on a portion of the caldera floor that subsided in 2018, that is emitting volcanic gas and steam. The caldera-wide ongoing gas survey will be compared to gas surveys done in the area prior to the 2018 collapse events and will reveal any changes in Kīlauea summit gas pathways and emissions. USGS photo by K. Mulliken on August 3, 2021.
On the north margin of the south sulfur bank, which was exposed during the Kīlauea summit collapse events in 2018, light-colored deposits are evidence of the ongoing alteration from volcanic gas emissions. Near the bottom of the photo, bright yellow sulfur deposits, which are a stark contrast to the darker gray basalt rocks, are further evidence of ongoing gas emissions in the area. USGS photo by K. Mulliken on August 3, 2021.
An HVO scientist uses a syringe to capture a sample from an area within Kīlauea caldera that was identified as emitting elevated levels of the volcanic gas carbon dioxide. The sample is transferred to a gas sample bag, which will later be taken to a lab for chemical analyses. USGS photo by K. Mulliken on August 3, 2021.
Stacked lava flows are visible in the wall of the down-dropped block, which was exposed during the Kīlauea summit collapse events in 2018. A small exposure of lighter-colored volcanic ash, likely the Keanakāko‘i tephra deposits erupted during Kīlauea's last explosive phase several hundred years ago, is visible beneath tens of meters (yards) of lava flows. USGS photo by K. Mulliken on August 3, 2021.
During the gas survey of Kīlauea caldera, HVO scientists walk transects in a grid-like pattern. As they traverse, the MultiGAS instruments that they are carrying on their backs measure the amount of carbon dioxide (CO2), sulfur dioxide (SO2), water vapor (H2O), and hydrogen sulfide (H2S). The measurements will be used to create a map showing the areas of the caldera floor where specific volcanic gasses are being emitted and their concentrations. USGS photo by K. Mulliken on August 10, 2021.
Spatter ramparts from the April 30, 1982, Kīlauea summit eruption remain visible on the floor of Kīlauea caldera. During this brief eruption, which lasted approximately 19 hours, lava erupted from a 1-km-long (0.6 mile) fissure that extended to the northeast of Halema‘uma‘u. Part of the 1982 spatter rampart collapsed into Halema‘uma‘u during the 2018 Kīlauea summit collapse events, but much of it remains intact. USGS photo by K. Mulliken on August 10, 2021.
From the northwest corner of the largest down-dropped block within Kīlauea caldera, HVO scientists were able to spot the southern edge of the lava lake that was recently active, from December 2020 to May 2021. The ongoing Kīlauea caldera gas survey is being conducted with permission from Hawai‘i Volcanoes National Park. Much of the survey is taking place within the hazardous closed area; HVO scientists wear hard hats and carry other safety gear such as gas masks and satellite communication devices. USGS photo by K. Mulliken on August 10, 2021.
Small amounts of Pele's hair, likely from the 2008–2018 Kīlauea summit lava lake, have accumulated in cracks and crevices on the floor of Kīlauea caldera. Pele's hair forms when lava becomes stretched, forming these long and thin strands of volcanic glass. This photo was taken in the eastern part of Kīlauea caldera, in an area that did not collapse in 2018. USGS photo by K. Mulliken on August 12, 2021.