CARBONATE FACIES ZONATION OF THE UPPER JURASSIC-LOWER CRETACEOUS APULIA PLATFORM MARGIN (GARGANO PROMONTORY, SOUTHERN ITALY)

The Late Jurassic-Early Cretaceous Apulia platform margin and the transition to adjacent basinal deposits (inner platform to basin) are well exposed in the Gargano Promontory. Detailed field work has allowed to recognize eight main facies associations which reflect various depositional environments, and which document a differentiated zonation, from the inner platform to the basin. A shallow lagoon existed in the internal part of the Gargano Promontory with a transition to tidal flat areas (F1). Oolitic shoals (F2) bordered this internal peritidal area passing seaward to a reef-flat with abundant corals (F3). A reef-front, associated with a coral rubble zone, has been found in some areas (F4). In the external margin zone, massive wackestones with Ellipsactinia occur (F5) and pass gradually to a rudstone facies on the proximal slope (F6). The base-of-slope facies association consists of pelagic sediments interbedded with gravity-displaced deposits (F7 and F8). The depositional profile of the Apulia Platform is typical of the Tethyan Jurassic-Early Cretaceous platforms, with slope declivities in the order of 25°-28°. The remarkable progradation of the platform in the northern tract of the Gargano (Lesina and Varano lakes area) and its substantial stability east- and southwards (Mattinata area) suggest a possible windward position of the margin in this latter portion and, in contrast, a leeward position of the northern portion.  &nbsp

CARBONATE FACIES ZONATION OF THE UPPER JURASSIC-LOWER CRETACEOUS APULIA PLATFORM MARGIN (GARGANO PROMONTORY, SOUTHERN ITALY)

The Late Jurassic-Early Cretaceous Apulia platform margin and the transition to adjacent basinal deposits (inner platform to basin) are well exposed in the Gargano Promontory. Detailed field work has allowed to recognize eight main facies associations which reflect various depositional environments, and which document a differentiated zonation, from the inner platform to the basin. A shallow lagoon existed in the internal part of the Gargano Promontory with a transition to tidal flat areas (F1). Oolitic shoals (F2) bordered this internal peritidal area passing seaward to a reef-flat with abundant corals (F3). A reef-front, associated with a coral rubble zone, has been found in some areas (F4). In the external margin zone, massive wackestones with Ellipsactinia occur (F5) and pass gradually to a rudstone facies on the proximal slope (F6). The base-of-slope facies association consists of pelagic sediments interbedded with gravity-displaced deposits (F7 and F8). The depositional profile of the Apulia Platform is typical of the Tethyan Jurassic-Early Cretaceous platforms, with slope declivities in the order of 25°-28°. The remarkable progradation of the platform in the northern tract of the Gargano (Lesina and Varano lakes area) and its substantial stability east- and southwards (Mattinata area) suggest a possible windward position of the margin in this latter portion and, in contrast, a leeward position of the northern portion.  &nbsp

Paleoecology and proliferation of the bivalve Chondrodonta joannae (Choffat) in the upper Cenomanian (Upper Cretaceous) Adriatic Carbonate Platform of Istria (Croatia)

Chondrodonta joannae (Choffat) is a morphologically variable oyster-like bivalve with a predominately calcitic shell. An exceptional exposure of C. joannae-bearing strata of late Cenomanian age crops out along the seaside in northern Istria (Croatia) and permits a taphonomical and functional analysis in order to define the life habit and growth strategies of this bivalve. The C. joannae population from the studied succession is characterized by highly-elongated, large and curved shells, reaching about 50 cm in height and 5 cm in length. This shell shape is typical of the club-like bivalve morphotype, which was adapted to soft-bottom substrates with high sediment accumulation. The shell is slightly inequivalve and characterized by a reduced body cavity, a few centimetres high, and a dorsal region up to 10 times longer. The shell opening mechanism was mostly based on the resilium located between the chondrophores which protrude in the body cavity. The abandoned dorsal cavity is filled by a calcite hinge plate, the ventral edge of which acted as fulcrum for the valve flexibility. In the hinge plate, the function of chondrophores changed. They acted as a hinge to keep tightly interlocked the valves, which considerably emerged above the sediment-water interface. The individuals were arranged in low shrub-type congregations, which produced low-relief mounds. The functional morphology and taphonomic signature suggest that C. joannae individuals collected food at a greater distance from the bottom with respect to the co-occurring rudists. We speculate that the C. joannae proliferation could be related to a late Cenomanian phase of environmental instability predating the OAE2 with fluctuating climatic conditions and ocean fertility

Sintesi delle conoscenze geologiche e stratigrafiche del Promontorio del Gargano

Negli ultimi decenni le conoscenze geologiche e paleontologiche del Promontorio garganico sono state notevolmente ampliate grazie al lavoro di numerosi ricercatori italiani e stranieri. Queste ricerche hanno permesso di conoscere con maggior dettaglio questo “piccolo” promontorio e la sua ricchissima geodiversità fatta di unicità geologiche, paleontologiche, strutturali e geomorfologiche di valenza internazionale. Nella comunità scientifica e anche nelle maggiori compagnie petrolifere il Gargano rappresenta un’area di riferimento per lo studio di sistemi carbonatici e per la comparazione di analoghi di superficie e di sottosuolo, anche in aree lontane come il Golfo del Messico, la Cina o il Medio Oriente. Questo articolo rappresenta un riassunto delle conoscenze attuali sui principali aspetti geologici e paleontologici del Gargano e un utile aggiornamento della letteratura disponibile, corredato di figure e quadri cronostratigrafici inediti

Internal waves as controlling factor in the development of stromatoporoid-rich facies of the Apulia Platform margin (Upper Jurassic-Lower Cretaceous, Gargano Promontory, Italy)

During the Late Jurassic, stromatoporoid-rich buildups were developed in south and intra-Tethys realms. These stromatoporoid buildups are mainly characterized by the high percentage of intraclastic-bioclastic debris, as main components of buildup bodies. However, the source of hydrodynamic energy resulted in debris production, is still a matter of debate. This study examines the Upper Jurassic-Lower Cretaceous stromatoporoid-rich buildups of Monte Sacro Limestones (MSL), Apulia Carbonate Platform (ACP), in order to describe the main carbonate facies along the study area, as well as the possible source of turbulence. Three main lithofacies have been distinguished: LF1 — stromatoporoid-rich facies with two subfacies (LF1-S1: floatstone with wackestone to fine-grained packstone, LF1-S2: rudstone-floatstone with intraclastic-bioclastic packstone-grainstone), LF2 — stromatoporoid-coral facies distributed in wackestone to packstone matrix (LF2-S1) and tabular stromatoporoid-corals surrounded by wackestone matrix (LF2-S2) and, LF3 — stromatoporoid-microbial facies. These facies were deposited along the mid part of a distally steepened ramp. The in-situ form of stromatoporoids was developed in a mud-dominated matrix (LF1-S1) under low-energy conditions while the intraclastic-bioclastic rich facies (LF1-S2) were deposited under a high-energy condition. The distribution of LF2 and LF3 in muddy matrix suggests occurrence of these lithofacies in quiet environments. The biotas were influenced by several factors including nutrient and light availability as well as by hydrodynamism. The stromatoporoid-rich buildups in ACP can be categorized as phototrophic-heterotrophic reefs generated in a pure carbonate environment. The light penetration was confined, resulted in the high development of light-independent micro-encrusters (Tubiphytes morronensis), in a mesophotic condition, where the environment was not ideal for light-dependent microencrusters (Lithocodium-Bacinella) to grow. We suggest that debris-dominated stromatoporoid-rich lithofacies (LF1) thrived in meso-oligophotic setting, along the nutricline and were affected by more than episodic high-energy events in a context where the surface waves were not effective. In such environments, internal waves can be an effective candidate to explain the episodic turbulences to produce the debris-rich facies of LF1-S2. Moreover, internal waves can pump the nutrient-rich waters to the buildups, and create an ideal setting where these metazoan communities thrived

Compilazione di carte paleogeografiche per l'individuazione di aree più promettenti allo sviluppo di reservoir carbonatici

Il progetto consiste nella sintesi di dati geologici e loro inserimento in un database, collegato ad un supporto GIS, che contenga tutti i parametri conosciuti relativi a tettonica, clima, chimismo delle acque e dell’atmosfera, rapporti isotopici, variazioni del livello del mare, eventi biologici ecc. (intesi come potenziali fattori di controllo). Il database, ottenuto dalla sintesi critica di un numero significativo di pubblicazioni scientifiche (articoli, special publication, monografie, tesi di dottorato), ottenute a loro volta da una revisione di oltre 40,000 articoli, conterrà tutte le informazioni utili alla caratterizzazione della piattaforma carbonatica in esame, con una struttura aperta che consenta di inserire la maggior parte di dati possibili. Lo scopo finale è di fornire un archivio uniforme di informazioni paleoambientali e deposizionali negli intervalli di tempo studiati (Cretaceo e Miocene) nell’area tetidea e in quella indo-pacifica

Stratigrafia e sedimentologia del margine della Piattaforma Apula nel Gargano (Giurassico superiore-Cretaceo inferiore)

Studio di dettaglio dei caratteri stratigrafici e sedimentologici delle successioni comprese tra il Giurassico superiore e il Cretaceo inferiore del margine della Piattaforma Apula affiorante nel Gargano. Misurazione e studio di diverse sezioni stratigrafiche in un transetto che comprende le facies di piattaforma interna, di margine, di scarpata e di bacino. Sono state ricostruite le varie associazioni di facies presenti e l'organizzazione stratigrafica della piattaforma

La Piattaforma Apula nel Promontorio del Gargano

Escursione geologica sul Promontorio del Gargano per illustrare e discutere l'organizzazione stratigrafica sedimentologica delle successioni comprese tra il Giurassico superiore e il Miocene. L'escursione della durata di tre giorni è stata organizzata per il Gruppo italiano dei Carbonati (Resp. Prof. Gloria Ciarapica) ed aperta sia ai Docenti di altre Università italiane che agli studenti di Dottorato. Il Dr. Morsilli ha curato sia gli aspetti scientifici della escursione che quelli logistici

New species of Peregrinella (Brachiopoda) from the Lower Cretaceous of the Gargano Promontory (southern Italy)

Two new Peregrinella species (P. garganica and P. fascicostellata) from the Lower Cretaceous Maiolica Formation of the Gargano Promontory (southern Italy) are proposed. The shells are allochthonous and occur in densely packed, gravity displaced accumulations that are intercalated within pelagic sediments. Preliminary data on the palaeoecology and palaeoenvironment of the Peregrinella beds confirm the suggestion that these brachiopods were the dominant component of cold-seep assemblages. The occurrence of ‘Rhynchonella’ peregrina (Buch) [junior synonym of Peregrinella multicarinata (Lamarck)], cited in the past literature on the area investigated, located NW of Mattinata, is not confirmed. The specimens collected present several features which are different from Lamarck’s species: the majority of them have a more convex shell, alae clearly separated from the lateral regions, and large deltidial plates. These specimens are here classified as P. garganica sp. nov. Other specimens, all collected from a single exposure, are characterized by having several orders of ribs forming a fascicostellate ornamentation, particularly accentuated in the central part of the valve; they are attributed to P. fascicostellata sp. nov