Late Maastrichtian Short‐term Biotic Events on Seymour Island, Antarctic Peninsula

The use of stratigraphic plane analysis, a new graphical technique to view simultaneously both spatial and stratigraphic distribution of biostratigraphic data, has documented important short-term oceanic events in the high southern latitudes during the Maastrichtian. Single-occurrence or restricted-occurrence horizons on Seymour Island using traditional one-dimensional (temporal) composite range charts have been viewed as artifacts of preservation or collection failures. When the Seymour Island data are evaluated from a spatial perspective using stratigraphic plane analysis, it is clear that these restricted-occurrence horizons are not due to collection failures or incomplete preservation but represent important biotic events, probably associated with widespread thermal events documented in the deep-sea record and to mid-Maastrichtian changes in sea level. These short-term events, in combination with the long-term decline in temperature at the end of the Cretaceous, may have been important contributory factors leading to the extinction event at the end of the Cretaceous.