intraclast

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intraclast A carbonate fragment of lithified, or partly lithified sediment, derived from the erosion of nearby sediment and redeposited within the same area (compare EXTRACLAST). Such reworked fragments are often amorphous and structureless. Carbonate lumps, formed by the complete micritization (see MICRITE) of shell fragments are indistinguishable from true intraclasts. They are, of necessity, classified with intraclasts, although clearly they are not true intraclasts.