acidic
activity
color
colored
cone
crystallization
crystals
deposit
emits
field
fumarole
fume
gas
gase
geology
geyser
hollow
hot
hydrothermal
island
kunashir
kuril
kurile
landscape
mendeleev
mineral
native
natural
nature
poisonous
slope
smoke
smoking
solfatara
steam
sulfide
sulfur
sulfurous
tephra
toxic
vapor
volcanic
volcano
yellow