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392 Facies (2007) 53:389–400
Fig. 3 Facies from the Carnian to Rhaetian Punta Bassano carbonate grey limestone. c Beige to whitish laminated mudstone with fenestrae.
succession. a Gray homogeneous limestone medium to thickly bedded. d Large fenestrate structures occurring towards the top of the succes-
b Abundant gypsum pseudomorphs on the weathering surface of the sion
Lithofacies type 2 MF4 Microbial laminated wackestone is the low-energy
facies (Fig. 4). The laminae are composed of alternating
This lithofacies represents a well-stratiWed beige to whitish layers of mudstone and very Wne-grained peloidal pack-
laminated mudstone with fenestral fabrics (Fig. 3c). These stone, in places grainstone. Fenestrae are abundant and
beds, 2–20 cm thick, are generally intercalated to the homo- often also include geopetal fabrics. The more thick laminae
geneous limestone (lithofacies type 1), at the top of the contain Xattened ostracod shells and remnants of echino-
shallowing-upward cycles. The fenestrae are Xattened and derms. Framboidal pyrite and bedding-parallel irregular
almost parallel to the bedding and to the undulate millime- microstylolites are also observed.
tre laminae. Towards the top of the succession, the voids
size increases, up to 5 mm (Fig. 3d). The laminated struc- MF5 Ostracod/peloidal packstone to grainstone is the
tures are sometimes discontinuous, interrupted by trough more high-energy facies (Fig. 4). These are made up of
stratiWcation underlined by mud drapes. alternating layers of almost exclusively double-valved
ostracods, lying parallel to the stratiWcation, and of dense
Two energy-controlled microfacies, normally alternated, micritic peloids of variable size. Other bioclastic grains are
have been recognised.
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