 Similar weathered regoliths exist at much higher latitudes – 35–42°S in southeast Australia (Victoria and Tasmania), 40–45°N in the United States (Oregon and Wisconsin) and 55°N in Europe (North Ireland, Germany) – although these are not regionally extensive.In some localities it is possible to relatively date saprolite by considering that the saprolite must be younger than the parent material and older than any thick cover unit such a lava or sedimentary rock.This principle is useful in some contexts but in others, like certain parts of Sweden where grus is formed from Precambrian rocks and overlain by Quaternary deposits, it is of little value.