The use of silt grain size parameters as a paleovelocity gauge: A critical review and case study

During the past decade, several reports have been published that infer paleovelocity of deep-sea currents from grain-size parameters of fine-grained sediments. Such inferences may be a gross oversimplification. Laboratory flume experiments and theoretical treatments of suspended sediment transport indicate that particles less than 30 μm in diameter are maintained in suspension by currents of less than 4 cm/sec. Also, there are several factors that influence sediment suspension other than velocity, of which velocity may be one of the least important.