Each wedge exhibits different characteristics and sedimentary patterns, thus displaying many incongruities and depositional unconformities. The Rice Lake wedge, for instance, achieves a peak of 180 m above sea level, with a 20 m layer of shallow surface Oak Ridges Moraine sediments, underlain by the "Newmarket Till". The other wedges, which peak at up to 335 m, have thicker and more varied surficial deposits, and the "Newmarket Till" lies deeper below the surface. Moreover, the sedimentary deposits are underlain by "Halton Till" on these wedges, which is not present in the Rice Lake wedge.