▁sul fur ▁depos its ▁are ▁found ▁at ▁the ▁sum mit . ▁Several ▁sul fur ▁mines ▁lie ▁in ▁the ▁complex . ▁One ▁mine ▁at ▁an ▁alt itude ▁of ▁ ▁was ▁opened ▁in ▁ 1 9 1 3 ▁and ▁remained ▁in ▁use ▁from ▁ 1 9 5 0 ▁to ▁ 1 9 9 2 . ▁It ▁was ▁the ▁world ' s ▁highest ▁mine ▁during ▁that ▁period . ▁Origin ally , ▁sul fur ▁obtained ▁at ▁the ▁mine ▁was ▁transport ed ▁down ▁with ▁llam as . ▁Sub sequently , ▁an ▁aer ial ▁cable way ▁was ▁employed ▁to ▁transport ▁the ▁sul fur ▁to ▁the ▁town ▁of ▁A min cha . ▁To ▁bring ▁the ▁sul fur ▁down , ▁a ▁road ▁network ▁to ▁the ▁sum mit ▁was ▁constructed ▁in ▁ 1 9 7 2 , ▁although ▁it ▁is ▁now ▁imp ass able . ▁ ▁In ▁ 1 9 8 6 , ▁four ▁men ▁were ▁reported ▁to ▁be ▁living ▁at ▁an ▁alt itude ▁of ▁, ▁making ▁them ▁the ▁highest ▁permanent ▁residents ▁on ▁Earth . ▁ ▁Geography ▁and ▁ge ology ▁ ▁Regional ▁setting ▁▁ ▁A uc an qu il cha ▁is ▁part ▁of ▁the ▁Central ▁Vol can ic ▁Zone ▁( CV Z ) ▁of ▁the ▁And es , ▁a ▁highly ▁sil ic ic ▁vol can ic ▁zone ▁in ▁South ▁America . ▁The ▁CV Z ▁generates ▁mag mas ▁at ▁a ▁rate ▁of ▁, ▁one ▁t enth ▁of ▁the ▁global ▁average ▁of ▁arc ▁mag ma ▁production , ▁and ▁lies ▁about ▁ ▁above ▁the ▁W ad ati – Ben io ff ▁zone . ▁The ▁arc