Backbeach asymmetrical wind ripples on biogenic aragonite sand.

Asymmetrical ripple marks have a long side and a short side, when viewed in cross-section. They form in a one-directional current by wind or water. The current direction was toward the short side of each ripple.

The asymmetrical ripples shown above are wind ripples, formed above the swash zone in a backbeach facies. The wind direction was from left to right, resulting in ripple marks with ridges perpendicular to shoreline and subparallel to wave movement directions.

Orientation: land is toward the top; ocean is toward the bottom.