9406506 D'Hondt PI and collaborators will test whether early Paleocene last occurrences of late Cretaceous planktic foraminifera primarily resulted from taxonomic survival or from sedimentary reworking across the Cretaceous-Tertiary (K-T) boundary; principal testing technique will be carbon-isotopic analyses of monospecific samples. Broader objectives are to determine how these last occurrences bear on gradual or catastrophic extinction scenarios, and on exogenous or endogenous causes of the K-T mass extinction. Study and results will also bear on a) geographic variation in survivorship, b) relation among survivorship, ecologic strategy, and production, and c) high-resolution biostratigraphy of the K-T boundary. ***
