Sedimentary structures, textures, and fabric were studied in eight graywacke beds exposed on the wavecut platform near Grande Vallee; these beds were traced continuously for 2 mi along the strike which is almost parallel with the average current direction indicated by sole marks.

The direction of current flow during deposition of the bed was determined from intrabed lineations and grooves, oriented graptolites, and grain fabric. Most beds show large deviations of internal flow directions from sole-mark directions, particularly in distal regions. Internal directions were increasingly divergent from the sole toward the top of the bed. Agreement between dimensional grain orientations and other internal flow-direction indicators proves that grain orientations are depositional, not tectonic fabrics, and that grains generally were oriented parallel with the flow and imbricated in an upcurrent direction. Current-normal orientation was found in a plane-laminated part of one bed. Grains tend to lack statistically significant preferred orientation in proximal parts of t e beds but show preferred orientation as the beds were traced distally.

These results suggest that existing concepts of turbidity-current flow are oversimplified and neglect the possibility of large changes in flow direction, perhaps caused by secondary currents within a single turbidity current.

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