REWORKED DOLOMITE CRUSTS IN THE WETTERSTEINKALK (LADINIAN, ALPINE TRIASSIC) AS INDICATORS OF EARLY SUPRATIDAL DOLOMITIZATION AND LITHIFICATION

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Abstract
SUMMARYDolomitic intraclastic sediments intercalated in a cyclic limestone‐dolostone sequence of the Wettersteinkalk represent a rock type with reworking fabrics demonstrating early lithification and dolomitization. The extreme flatness and the angularity of the pebble‐sized doloclasts, the lack in plastically deformed dolomitic fragments, and clasts of previously cementated arenites and oncolites testify to a pre‐reworking consolidation which, besides biogenic stabilization and dehydration, requires an early cementation. In the different types of doloclasts cementation both by dolomite and by calcite has been confirmed by stained peels and thin‐sections, electron‐microphotographs, and electron‐microprobe analysis.The prevailing rock type, a very poorly sorted mixture of doloclasts and minor amounts of rounded limeclasts with a pelletal calcite mud matrix is interpreted as storm sediment formed by the introduction of subtidal lime muds to dolomite incrusted supratidal flats.