Paleomagnetic results from the Carboniferous of North America: development of a chronostratigraphic marker horizon for Canadian east coast Carboniferous strata.

In results from Canadian east coast Carboniferous strata, an important time-stratigraphic horizon that could be of global significance can be recognized. Young Carboniferous units are all reversely magnetized, while older units may have normal, reverse, or (most frequently) dual-polarity magnetizations. It appears that the behaviour of the geomagnetic field changes drastically at some time in the Carboniferous, from frequent polarity changes during the early part to a constant polarity for the later part. The timing of this modal change can be used most effectively as a time line for correlation of units within and among Carboniferous basins. -from Authors