This study explores the paleoecological significance of richly diversified, predominantly arenaceous foraminiferal assemblages in Upper Cretaceous-Paleogene fine-grained elastics from the East Newfoundland Basin, Labrador Sea and North Sea Basin. The faunas resemble those commonly associated with flysch deposits in various parts of the world. The paleoecological and paleobathymetrical significance of flysch-type faunas, and the depositional environment of flysch sediments, have been topics of an extensive literature and encompass a wide divergence of opinion. For example, flysch-type faunas have been interpreted as indicators of great (oceanic) depth, of shallow, nearshore realms, and are being essentially related to potential hydrocarbon source rock. A recent recovery of rather similar agglutinated faunas in Upper Cretaceous-Paleogene deep sea sediments located above oceanic basement, has provided an independent means of making paleobathymetric estimates using age vs. depth subsidence curves. The method indicates that such fossil faunas occur at water-depths of 2.5 - 3.5 km, which may serve as a lower depth limit. A recently published model emphasizes the importance of a number of inter-related physico-chemical factors at or near the sediment-water interface in accounting for faunal distribution. This model, which appears to be a function of somewhat restricted circulation, may provide an adequate explanation for the extensive bathymetric range and variety of biotopes these agglutinated foraminiferal faunas are capable of inhabiting. Application of this model to the East Newfoundland Basin, Labrador Sea and North Sea agrees well with the postulated tectonic evolution and paleogeography of these regions and illustrates the use of these faunas for basin analysis.