fall ▁affected ▁most ▁of ▁New ▁Zealand , ▁with ▁an ▁ash ▁layer ▁as ▁thick ▁as ▁ ▁depos ited ▁on ▁the ▁Ch ath am ▁Islands , ▁ ▁away . ▁Later ▁er os ion ▁and ▁sed iment ation ▁had ▁long - last ing ▁effects ▁on ▁the ▁landscape , ▁and ▁may ▁have ▁caused ▁the ▁Wa ik ato ▁River ▁to ▁shift ▁from ▁the ▁Ha ur aki ▁Pla ins ▁to ▁its ▁current ▁course ▁through ▁the ▁Wa ik ato ▁to ▁the ▁Tas man ▁Sea . ▁Less ▁than ▁ 2 2 , 5 0 0 ▁years ▁ago , ▁Lake ▁T au po , ▁having ▁filled ▁to ▁about ▁ ▁above ▁its ▁current ▁level , ▁cut ▁through ▁its ▁O ru an ui ▁ign im br ite ▁dam ▁at ▁a ▁rate ▁which ▁left ▁no ▁terra ces ▁around ▁the ▁lake . ▁About ▁ ▁of ▁water ▁was ▁released , ▁leaving ▁b ould ers ▁of ▁up ▁to ▁ ▁at ▁least ▁as ▁far ▁down ▁the ▁Wa ik ato ▁River ▁as ▁Mang ak ino . ▁ ▁See ▁also ▁▁ ▁North ▁Island ▁Vol can ic ▁Pl ate au ▁ ▁H ate pe ▁er u ption ▁( T au po ▁Vol cano , ▁circa ▁ 1 8 0 ▁AD ) ▁ ▁References ▁▁ ▁Category : Pre histor ic ▁vol can ic ▁events ▁Category : P le ist oc ene ▁vol can ism ▁Category : T au po ▁Vol can ic ▁Zone ▁Category : Super vol cano es ▁Category : Events ▁that ▁forced ▁the ▁climate ▁Category : VE I - 8 ▁er u ptions ▁Category : Vol can ic ▁er u ptions