| Summary: | Soft-sediment deformation structures have been found in some upper Messinian transitional deposits, probably equivalent to the widespread Lago-mare event (Cita, 1978, Cipollari et al., 1999, Iaccarino & Bossio, 1999, Clauzon et al., 2005), named as “calcari di Fiumicello” in the new geological map (CARG Project, Morsilli et al., in press). This lithostratigraphic unit, about 30-40? meter thick, crops out in the northern part of the Gargano Promontory near Cagnano Varano (Fig. 1). Four detailed stratigraphic sections have been measured and sampled along some rail cuts (Fig. 2). The succession consists of an alternation of well bedded limestone, marly limestone, marls and lime mud, with few conglomerate layers. Limestone texture are made by ooidal (mainly dissolved and recrystallized) or intraclastic grainstone to packstone, arranged in 10 to 120 cm thick beds frequently cross laminated and cross stratified (current and wave ripple, bidirectional and sigmoidal lamination at dune scale, low angle planar laminations). Grain size range from fine to very coarse sand. Marly limestone and marls, white to light brown in colour, shows a variable bed thickness from 2 to 50 cm with very thin, mm-scale, even laminations. Conglomerate layers, mainly 5 to 15 cm in thickness, are visible in various intervals of the stratigraphic sections. They consist mainly of othoconglomerate with clasts up to 2 - 6 cm, derived from the Serravallian-Tortonian interval of the Pietra Leccese formation. Paraconglomerate with a sandy matrix are visible only at the top of the section 1 where the bed thickness increase up to 30 cm. Elongated clasts reach the maximum size of about 10 cm. Exposure surfaces are testified by thick root traces visible in the marly intervals and also in some conglomerate bed of the Section 3. Macrofossils are not visible in the measured sections and micofossils in thin sections are mainly reworked and consists of fragments of benthic and planktonic foraminifera. There are also some fossils not reworked as miliolids ...
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