1^ sessione RICERCA E COLTIVAZIONE DI IDROCARBURI IN BASILICATA E NEL BACINO DEL MEDITERRANEO
modera: Maurizio Lazzati
attilio sulli
The contribute of oil exploration in Sicily to produce new data and geological models A. Sulli Dipartimento di Scienze della Terra e del Mare, Università di Palermo, Via Archirafi 22, 90123 Palermo attilio.sulli@unipa.it Atti del 1º Congresso dell’Ordine dei Geologi di Basilicata,“Ricerca, Sviluppo ed Utilizzo delle Fonti Fossili: Il Ruolo del Geologo”, Potenza, 30 Novembre - 2 Dicembre 2012.
Oil exploration in Sicily started in the 1950s with promising discoveries in the eastern Sicily (Ragusa and GelaFields). Several exploration wells were drilled onshore, and the first borehole in Europe located in offshore was performed in Sicily (Gela,1959), followed by many other also productive wells. The exploration, at first allowed only to the public companies, was extended as well to minor and foreign companies. During the following fifty years the implementation of the geophysical techniques (mainly 2D and recently 3D seismic reflection profiles), calibrated by a large amount of boreholes, increased the geological dataset regarding the buried and submerged framework, both on land and offshore Sicily. The availability of these data accompanied the contemporaneous restless activity of the research institutions, which collected mainly detailed field data. The resulting work provided new insights intothe reconstruction of the geometric relationships of the rock bodies and yielded new stratigraphic and structural data, down to some thousands of meters, comprising the surrounding offshore areas, and produced an up-to-date geological model of Sicily. The collisional complex is composed of (Catalano et al., 1996): 1) a foreland, which outcrops in the south-eastern Sicily (Iblean Plateau) and is submerged in the Pelagian sea (Pelagian foreland); 2) a Late Pliocene-Pleistocene foredeep, partially buried by the frontal termination of the Gela Thrust System, between Gela and Catania and submerged in the Sicily Channel; 3) a complex E to SE vergent fold and thrust belt,thick more than 15 km, outcropping on land and submerged in the adjacent seas, formed by an European element (Kabilian-Calabrian Units), a Tethyan element (Sicilide Units) and an African element (Sicilian-Maghrebian Units). Field and geophysical data (Catalano et al., 2000; Bello et al., 2000), calibrated by boreholes and recently supported by a deep seismic reflection profile (Si.Ri.Pro., Accaino et al., 2011), revealed in the chain the main structural elements, deriving from the deformation of mainly Meso-Cenozoic carbonate successions, originally deposited in the African passive continental margin, and their Tertiary terrigenous covers. These structural elements form almost horizontal levels separated by regional detachments and lying on a presumably not involved northwarddipping crystalline basement. The lowest element results from a Meso-Cenozoic mostly carbonate platform S-vergent imbricate fan (Panormide, Trapanese and Saccense domains) overthrusting the Iblean foreland and the Pelagian offshore: it appears as the main bulk of the chain. The intermediate element is a wedge of flat-lying Meso-Cenozoic deep water carbonate thrust sheets (Imerese and Sicanian domains) overthrusting the deformed carbonate platform rock units. The overlying element is a wedge of nappes of deep water deposits (Sicilide domain) and detached Tertiary terrigenous cover of the carbonate units (NumidianFlysch). The highest element consists of syntectonic uppermost Miocene-lower Pleistocene clastics, which unconformably seal the whole underlying shortened tectonic units. The fold and thrust belt in Sicily appears as the result ofthe interference of shallow and deepseated compressional structures generated and developed at the different structural levels (Avellone et al., 2010; Albanese and Sulli, 2012). The shallow structures, characterized by duplex geometries, involved during the Late Miocene relatively thin deep-water units (Sicilide,
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The contribute of oil exploration in Sicily to produce new data and geological models Attilio Sulli
Imerese, Sicanian units), whichwere superimposed on thick platform carbonate units, along wide and originally almost flat floor thrusts.The deep-seated structures, characterized by highangle, transpressive ramps,and consisting of large, double-verging pop-up structures, involved during the Latest Miocene-Pleistocene thicker platform carbonate successions (Panormide, Trapanese, Saccense units). The floor thrust of the shallow structures was passively deformed by the subsequent growth of the underlying, younger deep-seated structures. During the Plio-Pleistocene the compressional events alternated with both extensional and strike-slip episodes, giving rise to the present morphostructural setting.
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References Accaino F., Catalano R., Di Marzo L., Giustiniani M., Tinivella U., Nicolich R., Sulli A., Valenti V., Manetti P. (2011). A crustal seismic profile across Sicily. Tectonophysics, 508, 52–61. Albanese C., Sulli A. (2012).Backthrusts and passive roof duplexes in fold-and-thrust belts. The case of Central-Western Sicily based on seismic reflection data.Tectonophysics, 514–517, 180–198 Avellone G., Barchi M.R., Catalano R., Gasparo Morticelli M., Sulli A.(2010).Interference between shallow and deep-seated structures in the Sicilian fold and thrust belt, Italy. Journ. of the Geological Society, 167, 109-126. Bello M., Franchino A., Merlini S. (2000).Structural model of Eastern Sicily. Mem. Soc. Geol. It., 55, 61–70. Catalano R., Di Stefano P., Sulli A., Vitale F.P.(1996).Paleogeography and structure of the central Mediterranean: Sicily and its offshore area. Tectonophysiscs, 260, 291–323. Catalano R., Franchino A., Merlini S., Sulli A.(2000).Central Western Sicily structural setting interpreted from seismic reflection profiles. Mem. Soc. Geol. It., 55, 5–16.
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30 NOVEMBRE > Potenza 01 DICEMBRE > Potenza 02 DICEMBRE > Marsico Nuovo
CONGRESSO DEI GEOLOGI DI BASILICATA
RUOLO DEL GEOLOGO
1° CONGRESSO DEI GEOLOGI DI BASILICATA
RICERCA, SVILUPPO ED UTILIZZO DELLE FONTI FOSSILI
IL RUOLO DEL GEOLOGO
ATTI DEL CONGRESSO ORDINE DEI GEOLOGI DI BASILICATA
www.geologibasilicata.it/ http://congresso.geologibasilicata.it/2012/
SEGRETERIA ORGANIZZATIVA ORDINE DEI GEOLOGI DI BASILICATA Via Zara 114 - Potenza Tel: 0971.35940, Fax: 0971.26352 congresso@geologibasilicata.it Responsabile: Sig.ra Angela Rubolino
Con l’Alto Patronato di:
Presidenza della Repubblica Italiana E il Patrocinio di: Presidenza del Consiglio dei Ministri
Sponsorizzato da:
Ministero dello Sviluppo Economico
PRESIDENZA DEL CONGRESSO Dott. Raffaele Nardone RESPONSABILE ATTI CONGRESSUALI Dott. Raffaele Nardone
COMITATO PROMOTORE| Geol. Carlo Accetta, Geol. Raffaele Carbone, Geol. Filippo Cristallo, Geol. Franco Guglielmelli, Geol. Domenico Laviola, Geol. Maurizio Lazzari, Geol. Raffaele Nardone, Geol. Nunzio Oriolo, Geol. Mary William COMITATO ORGANIZZATORE|Geol. Raffaele Nardone - Coordinatore, Geol. Annamaria Andresini, Geol. Maurizio Lazzari, Geol. Nunzio Oriolo, Geol. Mary William COMITATO SCIENTIFICO|Dott. Raffaele Nardone - Coordinatore, Dott. Fabrizio Agosta, Dott. Mario Bentivenga, Dott. Claudio Berardi, Dott. Gerardo Colangelo, Ing. Ersilia Di Muro, Arch. Vincenzo L. Fogliano, Dott. Ivo Giano, Dott. Fabrizio Gizzi, Dott. Vincenzo Lapenna, Dott. Maurizio Lazzari, Dott. Sergio Longhitano, Ing. Maria Marino, Prof. Marco Mucciarelli, Dott. Lucia Possidente, Prof. Giacomo Prosser, Prof. Marcello Schiattarella, Prof. Vincenzo Simeone, Prof. Marcello Tropeano, Dott. Maria Pia Vaccaro, Dott. Donato Viggiano.
Tre intense giornate di sessioni ed interventi organizzate per i tecnici di tutti gli Ordini e Collegi, Operatori del settore Oil&Gas, Top Manager, Amministratori, Dirigenti e Funzionari della Pubblica Amministrazione, Studenti. L’obiettivo primario è quello di focalizzare l’attenzione sul ruolo che il geologo ha assunto in relazione allo sfruttamento compatibile e sostenibile delle fonti fossili naturali. La tematica verrà affrontata grazie all’intervento di relatori di altissimo livello tecnico ed istituzionale, con interessanti d i b a tti ti e d una t a v o l a ro to nd a su lla ge s t io n e ambientale e formazione professionale .
Proprietà letteraria riservata Editore 1a edizione: 2013
Tutti le immagini sono il frutto della ricerca dei relatori e quindi sono utilizzate in questa pubblicazione ad esclusivo scopo didattico e divulgativo.