ABSTRACT

"Deficiencies" of clastic particles in the ranges 1 to 4 mm and 0.125 to 0.062 mm have been widely reported in the literature. Reanalysis of the evidence cited as demonstrating the existence of these "deficiencies" reveals that (1) only a small number of data sets from a relatively few environments and localities have been considered, (2) some data sets have been misinterpreted, (3) a large body of contrary evidence has been ignored, and (4) statistically rigorous techniques were not used.

In an effort to remedy some of these shortcomings 11,212 analyses of sediment from a wide variety of localities and environments (glacial, fluvial, eolian, lacustrine, marine, estuarine, beach and other) were averaged in subsets and examined for evidence of the "deficiencies." Most of the subset histograms do not have the histogram valleys that were thought to prove the existence of "deficiencies," nor does the overall average histogram. All of the distributions plot as a series of (1 to 4) straight line segments on normal probability paper as does the overall average. This conformity to a model that has been proposed as the expected distribution for individual analyses further refutes the hypothesis of "deficiencies." Because the data represent such diverse environments and localitie it is suggested that the character of the plots is controlled by the nature of parent material and the effects of attrition rather than by depositional mechanism.