wave-ripple cross-lamination

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wave-ripple cross-lamination The form of cross-lamination (see CROSS-STRATIFICATION) produced by the migration of wave-generated ripples, or combined flow ripples (i.e. ripples formed by a combination of wave action and unidirectional flow). Wave-ripple cross-lamination is characterized by a variety of distinctive features, including: unidirectional cross-laminae, sometimes with drapes (sand laminae) oriented in the opposite direction; lensoid and complexly interwoven cross-sets; irregular, undulatory bases to cross-sets; and laminae which are discordant with the external ripple form.