over millions of years, alluvial deposits (eroded from the mountains by rivers) formed the vast canterbury plains in the south island and a number of smaller plains
In ka badan waqti dheer, dukaamada alluvial (oo ka kala go'ay buuraha durdurrada) waxay qaabeeyeen Bannaanka weyn ee Canterbury ee Koonfurta Jasiiradda iyo beero kala duwan oo aad u yar oo woqooyiga ah.