Paleocurrent

• Unidirectional, which give a clear, single direction of flow
• Bidirectional, which give a good linear direction, but it is unclear which direction along the linear trend the water flowed.

Unidirectional

• Cross-bedding – the axis of a trough cross bed or the down-dip direction of a tabular cross bed point the direction of paleo flow.
• Current ripple marks – will have the short side of the ripple pointing down stream.
• Sole markings/flute casts – the short, steep side will point up stream, and the long, tapered side points down stream.
• Imbrication – clasts line up in the direction of flow.

  Bidirectional

• Symmetrical ripple marks – flow is perpendicular to the ridge crest.
• Tool mark – flow is along the mark.
• Parting lineations – flow is along the grains.