The shores of Lake Pukaki offer clues to the formation of the landscape. In this embankment, which has been exposed through erosion, many layers of sediments deposited at various times and under various conditions of the area are shown. The layers, which were deposited indirectly through glacial action, are not the typical glacial deposits of moraines. These beds were formed in fluvial outwashes from the glaciers as they expanded and retreated at various times.