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October 20, 2020

Direct gas sampling at Sulphur Banks on September 30, 2020

Color photograph of two scientists sampling a volcanic fumarole
As part of routine monitoring efforts, HVO gas scientists collected helium samples from fumaroles in the Sulphur Banks, or Ha‘akulamanu, area of Hawai‘i Volcanoes National Park on September 30, 2020. Helium can pass through the glass of typical gas sampling bottles, so copper tubing is necessary for the specialized sample. Ratios of different helium isotopes tell scientists if the source of helium is deeper (from the mantle) or shallower (from the crust). USGS photo by T. Elias.
Photograph of tubing inserted into a fumarole
Tubing inserted into a fumarole at the Sulphur Banks in Hawai‘i Volcanoes National Park allows HVO gas scientists to sample gas. The gas travels through the tube into gas sampling bottles for later analyses. USGS photo by M. Warren.


Color photograph of native sulfur crystals
Different sulfur gases, including sulfur dioxide (SO2) and hydrogen sulfide (H2S), can react with each other to deposit crystals of pure native sulfur at sites of degassing called fumaroles. The crystals picture here formed within a Sulphur Banks area fumarole in Hawai‘i Volcanoes National Park. USGS photo by T. Elias.
Color photograph of yellow native sulfur crystals
A close-up image of native sulfur crystals that formed within fumaroles at the Sulphur Banks in Hawai‘i Volcanoes National Park. In addition to sulfur species and other gases, volcanoes emit water vapor. Here, some of the vapor has condensed to liquid water and formed droplets visible on the sulfur crystals. USGS photo by P. Nadeau.