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