Current · Cross section

Hummocky cross-stratification

Gently undulating laminae forming low mounds (hummocks) and hollows (swales) that cut across one another, with long wavelengths (about 1–5 m) and low heights.

How it forms

Large storms, through combined one-way and oscillatory flow.

Typical setting

Shelf below fair-weather wave base and above storm wave base

Way up

Not commonly used.

Flow direction

No. The mounds have no preferred orientation.

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