About: http://webisa.webdatacommons.org/339178864

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Like most volcanoes, the majority of gas emitted at Mount St. Helens is water vapor (H2O), followed next by carbon dioxide (CO2), and sulfur gases, including sulfur dioxide (SO2) and hydrogen sulfide (H2S).
http://www.w3.org/ns/prov#wasQuotedFrom	usgs.gov