PRESERVATION OF PLANAR LAMINAE DUE TO MIGRATION OF LOW-RELIEF BED WAVES OVER AGGRADING UPPER-STAGE PLANE BEDS - COMPARISON OF EXPERIMENTAL-DATA WITH THEORY

Experimental studies of the formation of planar laminae by migration o f low-relief bed waves over aggrading upper-stage plane beds show that the average thickness of laminae at a point increases with both aggra dation rate and the variance of the heights of bed waves passing that point. In general, the preserved laminae represent only a small propor tion (generally less than 50%) of the height of the largest bed waves in the population. The theory developed by Paola & Borgman (1991), rel ating the probability density function of stratal thickness to that of bed wave height for the case of no net aggradation, was adapted for a ggrading conditions and shown to agree well with data. These results s uggest that the theory can be used to estimate, from the distribution of thickness of planar laminae, either the distribution of bed wave he ights, mean aggradation rate, mean bed wave length or mean bed wave ce lerity, provided the other parameters can be estimated.