Late quaternary deposits of the Christchurch metropolitan area

摘要: Summary Deep wells sunk for artesian water beneath Christchurch penetrate three formations. The youngest, the Formation, consists of marine, estuarine, and fluviatile deposits which at least upper part was formed during post-glacial rise sea-level. It extends down to more than 200 ft below present sea-level, radiocarbon dates record sealevel, from — 73 9400 years ago (S83/501) 12 6100 (S84/523). Other dates, together with topographic soil evidence, are interpreted as indicating 'Subsequent period development by Waimakariri River a fan gravel over area, probably completed about 2,000 when sea-level little higher present. aggradation surface this is termed Yaldhurst Surface. Riccarton Gravel, on whose eroded Chri~tchurch Formation lies, thought be sub-surface representative that forms an earlier fan, 'surface—the Ha...