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Detailed sedimentological analysis of Aptian/Albian shallow water carbonate platform strata from Monte Faito, southern Italy, reveals composite sea-level change. The organization of the lithofacies and their related diagenetic overprint have allowed the identification of 50 elementary cycles. They often show exposure-related diagenetic features superimposed on subtidal deposits, suggesting drops of relative sea-level. Elementary cycles are grouped into 16 bundles forming 6 superbundles. The hierarchical organization of the cycles are interpreted as related to composite eustatic sea-level fluctuations driven by the Earth’s orbital perturbation in the Milankovitch frequency band. Moreover, the systematic variation of superbundle thickness and the general evolution of the lithofacies reflects variations of accommodation potential defining longer-term environmental changes. Different lithofacies forming elementary cycles are frequently separated by bedding planes that, when viewed in a sequence stratigraphic context, are interpreted as transgressive surfaces, maximum flooding surfaces or sequence boundaries. This allows the recognition of lowstand, transgressive and highstand deposits in the cyclic units. Considering both the bundle/superbundle ratio and the sequence stratigraphic interpretation of the superbundles, a chronostratigraphic diagram illustrating both gaps at bundle level and their expected location along the section was created. It establishes that the section developed over about 2.4 My.

A microstratigraphic analysis of a shallow water carbonate succession of Aptian age, cropping out at Monte Tobenna (southern Apennines, Italy), has allowed the recognition of eight lithofacies grouped into four lithofacies associations that imply inner carbonate platform environments. A sedimentological study on a 32-m-thick section, carried out on a centimetre scale, reveals a clear cyclic organization of the lithofacies; 7 to 135-cm-thick beds, frequently alternating with cm-thick green clayey levels, de®ne the 53 recognized cycles. Each cycle represents an Elementary Depositional Unit (EDU)whose vertical lithofacies evolution generally records either a transgressive-regressive trend (T/REDUs)or a regressive trend (R-EDUs). Generally, features related to emersion are represented by small dissolution cavities with geopetal ®lling. Early diagenetic processes in a vadose zone commonly characterize the subtidal deposits forming the EDU tops. Finally EDUs formed by sediment representing a same sub-environment (aggradation) and showing emersion-related features on top(A-EDUs) have also been recognized in the succession. The vertical organization of recognized lithofacies and related early diagenetic overprint clearly point to oscillations of depositional environments repeatedly interrupted by emersion, suggesting high-frequency relative sea-level oscillations. The measured succession includes the well known Orbitolina level which represents an important biostratigraphic marker horizon of southern Apennine carbonate platform deposits of Aptian age. In the ®rst 20 m of the studied section the EDU stacking leads to 10 bundles of a higher order (average thickness ˆ 205 cm) composed of 2-5 elementary cycles. In turn the recognized bundles join into 2 superbundles formed by 4 and 3 bundles with thicknesses of 753 cm and 549 cm respectively. The EDUs display a hierarchical stacking probably related to composite eustatic sea-level fluctuations in the Milankovitch frequency band. By contrast, a few metres above the Orbitolina level it was not possible to recognize any hierarchical organization of EDUs, and both fresh/brackish water deposits and green clayey levels reach their greatest abundance, testifying to a possible long-lasting relative low stand of sea-level and consequent cycle condensation. Nevertheless, some EDUs, composed of restricted lagoonal deposits, record higher frequency sea-level oscillations temporarily allowing for subtidal conditions. Unlike other Cretaceous intervals in the southern Apennines, data obtained from spectral analysis of the hierarchically organized portion of this sequence do not always agree with data from cyclostratigraphic analysis, probably because the sequence discussed does not represent a continuous record of the sedimentary processes, and also because phenomena such as amalgamation and condensation cannot be easily detected by mathematical treatment of sedimentological data. Therefore, spectral analysis of such shallow water carbonate successions should be used carefully and in conjunction with other techniques.

Vengono illustrati in questa nota alcuni risultati preliminari della crociera oceanografica condotta dall'Istituto di Ricerca Geomare Sud del CNR di Napoli a bordo della N/O Urania nell'agosto 1994. Questa indagine, svolta in aree selezionate dell'offshore pugliese tra Brindisi e S. Maria di Leuca si inquadra in un più ampio contesto di un programma di ricerca multidisciplinare dedicato allo studio delle aree di piattaforma continentale dell'Italia meridionale ed è stato sviluppato nell'ottica di un confronto tra il record geologico e morfologico del Pleistocene-Olocene e l'ambiente biologico e fisico attuale.

We describe a new terrestrial, plant-rich Fossil-Lagerstatte discovered at Magliano Vetere (Campania region, S Italy) in the middle Cenomanian of the Apennine Carbonate Platform. The deposit, 1.42 m thick, is made up of a thin-bedded interlayering of evenly laminated dolomicrites, lenticular dolorudites and carbonaceous seams, which contain well-preserved remains of terrestrial plants yielding cuticles and minor fishes. This study focuses on plant remains, to provide systematical, taphonomical and palaeoenvironmental considerations; nevertheless, a preliminary analysis carried out on fossil fishes has led to the identification of pycnodontids and teleosts. The Fossil-Lagerstatte retains sterile foliage-bearing shoots with epidermal features belonging to the genus Frenelopsis of the extinct conifer family of the Cheirolepidiaceae. Plant remains possibly represent a stable biotope, as floral composition displays no variation along the deposit. Nevertheless, episodes of harsh environmental conditions occurred as demonstrated by a fish mortality event and Ca-sulphate evaporite precipitation. Taphonomical considerations and sedimentological evidence from the encasing sediments suggest a parautochthonous deposition of fossil plants in a supratidal/intertidal mudflat, including a salt-marsh that was characterised by a restricted sea-water circulation, deposition of primary dolomite and episodical wildfires. The presence of xeromorphic features in Frenelopsis from Magliano Vetere could represent an adaptation to haline environment which was subjected to microtephra supply from a distant, orogenic volcanism. The facies evolution of the studied Fossil-Lagerstatte records a rapid regressive and a following slower transgressive trend, and constitutes the lowermost portion of a ~20 m thick interval characterised by several dolomitic plattenkalk, up to 1.50 m thick, which are separated by cyclically stacked peritidal limestones. We infer that: 1) the ~20 m thick, Plattenkalk-bearing interval represents a Sequence Boundary Zone in the stratigraphical record of the middle Cenomanian ApCP; 2) Frenelopsis thrived at the verge of an arid–semiarid climatical phase during a major pulse of relative sea-level fall.

This study reports an integrated facies analysis carried out on a new section from the Upper Aptian of the SE Matese Mts. (Civitella Licinio, northern Campania, S. Italy), which includes several decimeter-to-meter scale lacustrine intervals straddling a meter-scale plant-rich Plattenkalk. These intervals are assigned to the late Gargasian–early Clansayesian by their stratigraphic relationship with the upper Salpingoporella dinarica acme as well as lithologic and biostratigraphic supra-regional key-markers found in the Apennine Carbonate Platform (ApCP), including the Orbitolina Level. We infer that the monogeneric parautochthonous plant remains (Frenelopsis sp.) were deposited in a supratidal-to-paralic coastal mudflat close to a restricted, shallow-marine lagoon, at the verge of an arid–semiarid climatic phase. The Plattenkalk was rapidly replaced by persistent lacustrine lithofacies at the onset of a major climatic turnover (Glacial Trigger). The overlying shallow-marine deposits are capped by a deeply incised palaeokarstic surface and, in turn, by unconformable middle Clansayesian transgressive shallow-marine deposits. Interlayering of reliable lithologic indicators of palaeoclimate and High-Resolution Event Stratigraphic (HIRES) correlation of the Civitella Licinio succession with the astrochronologically tuned Mt. Faito reference section of the ApCP bring evidence of rapidly fluctuating hydroclimatic conditions (wet and arid phases) in the short (100 ky) and long (400 ky) eccentricity time band. HIRES and astrochronological age assignment to crucial key markers and humid/arid phases at Civitella Licinio permit to further refine the detailed stratigraphy of the Mt. Faito reference section and to assign the upper S. dinarica acme of the ApCP to a numerical age of 118.55–118.50 My. SEM and EDS analyses document common to abundant windblown volcanic particles (glass shards and sanidine crystals) throughout the Frenelopsis-rich Plattenkalk (~ 118.3 to ~ 118.2 My) and the encasing units, especially in the overlying brackish–lacustrine deposits. Palaeogeographic and palaeoclimatic reconstructions suggest that the pyroclastic material was probably transported by northeasterly trade winds from orogenic volcanic centers located within the Dinaridic–Carpatho-Balkan arc–trench system and have been supplied to the ApCP for a time span of ~ 3 My during the Late Aptian. A preliminary tephrostratigraphic correlation of the Upper Aptian volcaniclastic levels of the ApCP with the bentonite levels of the Vocontian Basin is proposed.