Stratigraphy of the Cambrian

Despite the long recognition of its distinction from younger Ordovician rocks and older Precambrian rocks it was not until 1994 that this time period was internationally ratified. The base of the Cambrian is defined on a complex assemblage of trace fossils known as the Treptichnus pedum assemblage.[10] Nevertheless, the Treptichnus pedum, a reference ichnofossil for the lower boundary of the Cambrian, its usage for the stratigraphic detection of this boundary is always risky because of occurrence of very similar trace fossils belonging to the Treptichnids group well below the T. pedum in Namibia, Spain and Newfoundland, and possibly, in the western USA. The stratigraphic range of T. pedum overlaps the range of the Ediacaran fossils in Namibia, and probably in Spain
______________
TN Mortgage Rates
hoa property management