Аннотация:The settling velocities of empty tests of planktonic foraminifera have been determined experimentally, using tests both from sediment samples and from combusted plankton samples. The modal settling velocity of the species studied was equivalent to that of a quartz sphere of diameter approximately 2.4 times less than the maximum diameter of the foraminifera. Large variations from this mode occur and result from varying test shapes and wall thicknesses. The sequence of foraminifera in graded beds corresponds closely to their settling behavior determined experimentally. The significance of this new information for the production, dissolution, and redistribution of foraminiferal tests is considered briefly.
