Sedimentary structures of two modern point bars on a meandering part of the Red River near Shreveport, Louisiana, were investigated by trenching. On one of them, the Beene point bar, 12 sets of trenches, 2-8 feet deep, were dug with a tractor-powered shovel. The trenches ranged from 25 to 250 feet long, and were dug in T-shaped and X-shaped patterns. The point bars consist mainly of fine-grained, well sorted sands, commonly interbedded with and overlain by thin silt layers. Gravelly sands occur in the deeper parts of some of the trenches.

The most abundant type of sedimentary structure is trough (or festoon) cross stratification. Individual trough sets range in size from 1 cm. thick, 5 cm. wide, and 15 cm. long, to at least 1.5 feet thick, 8 feet wide, and 33+ feet long. In any one section, the size of the trough sets tends to decrease upward. The smaller sets are "microtrough" ripple laminae, and occur in the siltier sands and silts. The surface expressions of these ripple laminae appear to be cuspate ripples. The longitudinal axes of trough sets measured at 8 different localities on the Beene point bar have a strong preferred orientation parallel with the local, adjacent, stream flow direction. The resultant vectors obtained by summing observations on individual cross-stratification planes at each locality also point downstream, but have much weaker magnitudes because of the variability associated with the diverse orientations of cross strata within any individual set. In addition to the cross-stratified sands, beds containing parallel, horizontal laminae also occur locally in the siltier sands.

Spoon-shaped depressions on the surfaces of the bars, oriented with the tips of the "spoons" pointing downstream, may represent scours incompletely filled with trough-shaped cross laminae. At the upstream end of one of these scours, cross-laminae in the upper part of the sand which partially fills the scours are overturned downstream. Overturning occurred before deposition of any overlying strata and probably during rapid subsidence of river level.

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