Inthe1960s,whilestudyingthevolcanichistoryofYellowstone...
04-24
问题详情:Inthe1960s,whilestudyingthevolcanichistoryofYellowstoneNationalPark,BobChristiansenbecamepuzzledaboutsomethingthat,oddly,hadnottroubledanyonebefore:hecouldn'tfindthepark'svolcano.Ithadbeenknownfo...