Assertion: hydrogen sulfide | /r/AtLocation | volcano
Facets:
value: naturally
type: MANNER
value: geologically
type: MANNER
Source sentences:
text: Hydrogen sulfide also occurs naturally in sewers, manure pits, well water, oil and gas wells, and volcanoes.
text: Hydrogen sulfide is most often present in high iron bearing water and low or acidic pH waters, but also occurs naturally in crude oil, natural gas, and geologically active areas like volcanoes and hot springs.