Excellent exposures of the Middle Ordovician Cloridorme Formation in the northern Gaspe permit correlation up to 7.5 km and well-defined units up to 10.5 km in the direction of current flow. Flutes and grooves are the most abundant directional structures, the groove orientation being more variable than that of the flutes. The variability of direction indicators is greater in graywacke, and greater vertically than horizontally in the same bed. Few longitudinal trends were detected, but locally eroded fragments of finer-grained sediments are important as textural elements, as tools, and as erosional indicators. Individual graywacke and calcisiltite beds are very discontinuous in longitudinal section. A volume of 10 to 30 X 10 6 m 3 is estimated for an average graywacke bed.

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