He drew attention to Manuherikia Group sediments on the top of mountain ranges, and to the observation that sequences in distinct basins were similar.

His conclusion was that the Manuherikia Group is the result of sedimentation in a single (except for the earliest stages) very large basin that was later intruded by the growth of the mountain ranges.

The oldest unit of the Manuherikia Group is the Saint Bathans Member of the Dunstan Formation, consisting of the braided-river fill of valleys incised into the basement rocks.

The St Bathans paleovalleys eventually filled, sedimentation spread out over a broader area, and the fluvial character became dominantly meandering.

Fully lacustrine conditions ensued with the submergence of these deltas and for much of the mid Miocene, Lake Manuherikia was without known bounds.

Rising mountains in the Late Miocene-Pliocene eventually deluged Lake Manuherikia with gravel – the Maori Bottom, or Maniototo Conglomerate.