▁has ▁migr ated ▁east ward ▁towards ▁the ▁high ▁And es ▁from ▁the ▁Pacific ▁Ocean ▁coast ▁since ▁the ▁Jur ass ic . ▁The ▁arc ▁contains ▁and es it ic ▁vol cano es , ▁ign imb rit es ▁and ▁comp ound ▁vol cano es ▁and ▁has ▁generated ▁over ▁ ▁of ▁er u ption ▁products ▁over ▁ 2 8 ▁million ▁years . ▁ ▁The ▁A uc an qu il cha ▁complex ▁lies ▁north west ▁of ▁the ▁Al ti pl ano – P una ▁vol can ic ▁complex ▁( AP VC ), ▁a ▁local ▁large ▁ igne ous ▁province . ▁The ▁AP VC ▁is ▁under p inned ▁below ▁at ▁a ▁depth ▁of ▁ ▁by ▁a ▁slow ▁se ism ic ▁velocity ▁zone ▁that ▁has ▁been ▁linked ▁to ▁the ▁presence ▁of ▁ 1 5 – 2 5 % ▁of ▁partial ▁mel ts ▁in ▁the ▁zone . ▁The ▁A uc an qu il cha ▁complex ▁is ▁much ▁smaller ▁vol um etr ically ▁than ▁the ▁AP VC ▁ign imb rit es , ▁but ▁the ▁duration ▁of ▁activity ▁and ▁the ▁location ▁indicate ▁that ▁A uc an qu il cha ▁is ▁a ▁sub component ▁of ▁the ▁AP VC ▁complex . ▁ ▁The ▁long - term ▁mag ma ▁output ▁of ▁A uc an qu il cha ▁is ▁compar able ▁to ▁the ▁mag ma ▁output ▁of ▁other ▁long - term ▁active ▁vol cano es ▁in ▁the ▁central ▁And es ▁such ▁as ▁O ll ag ü e ▁and ▁L l ulla illa co . ▁In ▁all ▁such ▁cases , ▁an ▁early ▁peak ▁in ▁mag ma ▁output