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.