Further down, large sections of sandy sedimentation reveal a time during the last glacial period when sea levels were around 125m below where they are now, and a landbridge connected what is now the North and South Islands. These discoveries were coming out of a commercial project designed to give a new building on Whitmore St in the centre of the CBD the best possible foundations. Environmental consultancy firm ENGEO were analysing samples taken from 10 bores on the site, and specialist Dr Matt Ryan soon realised there were telltale signs of internationally significant geological events. Ryan has a Ph.D from Victoria University of Wellington in geology focusing on analysing paleo vegetation and saw in one of the samples what appeared to be evidence of supervolcanic ash.