| Summary: | Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution December 1987 Cenozoic (predominantly Paleogene) "flysch-type" agglutinated foraminiferal assemblages and their modern analogs in the North Atlantic and adjacent areas have been studied to provide an overview of their spatial and temporal distribution and utility for paleoenvironmental analysis. Over 200 species of agglutinated foraminifera have been recognized in Paleogene sediments from North Atlantic and Tethyan basins. This unified taxonomic data base enables the first general synthesis of biostratigraphic, paleobiogeographic and paleobathymetric patterns in flysch-type agglutinated assemblages from upper Cretaceous to Neogene sediments in the North Atlantic. The majority of taxa are cosmopolitan, but latitudinal, temporal and depth-related trends in diversity and species composition are observed among flysch-type assemblages. Modern deep-sea agglutinated foraminiferal faunas provide an analog to fossil flysch-type assemblages and serve as models for paleoecologic studies. Core-top samples from the Panama Basin, Gulf of Mexico and Nova Scotian continental rise were examined in order to determine the habitats of modern species of agglutinated foraminifera. The ecology of modern taxa provides constraints on the paleoenvironmental significance of fossil agglutinated assemblages in the North Atlantic, and their utility for paleoceanography. Towards this end, spade core samples from a 3912 m deep station in the Panama Basin were studied to determine abundance and microhabitat partitioning among living agglutinated foraminiferal populations and the preservation of dead assemblages. The genera Dendrophrya, Cribrostomoides and Ammodiscus have epifaunal habitats and the genus Reophax is predominantly infaunal. Species of Reophax are probably responsible for fine reticulate burrows observed in xradiographs. An experiment using ...
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