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Vengono illustrati in questa nota i risultati preliminari di due crociere oceanografiche condotte nell'offshore tirrenico dall'Istituto di Ricerca Geomare Sud del CNR di Napoli a bordo della N/O Urania rispettivamente nell'ottobre 1992 e nel maggio 1993. Le ricerche effettuate sono inserite in un progetto di ricerca che il Geomare sta conducendo da alcuni anni sul tema "Stratigrafia e strutture dell'offshore tirrenico", articolato in vari sottoprogetti che prevedono lo studio di aree selezionate dei mari circostanti l'Italia meridionale tramite sismica monocanale di alta risoluzione.

The structural and stratigraphic framework of Puglia offshore between the Gargano promontory and the town of Brindisi (southern Adriatic Sea) has been analysed based on 1700 km of multichannel seismic profiles and 10 exploratory wells. The area includes two different geodynamic settings: (1) part of the undeformed Apenninic foreland ("Apulian carbonate Platform"), consisting mainly of shallow water Mesozoic carbonates, and (2) part of the southern Adriatic Basin, which represents the foredeep of the Hellenic thrust system. A Mesozoic slope, buried by Tertiary clastics and corresponding to the edge of the Apulian carbonate platform, is observed on seismic data. The present physiography of the escarpment is the result of an erosional retreat mainly developed during the Tertiary and related to the subsidence of the South Adriatic Basin; at the same time carbonate facies belts, as evidenced by well data, seem to suggest that in some sectors of the margin the original Mesozoic physiography has been preserved and fossilized, Three seismostratigraphic units, separated by regional or local unconformities, have been distinguished in the Neogene clastic sequence of the South Adriatic Basin. Significant deformations in the sedimentary cover are represented by various antiforms. One of these antiforms, named the "Gondola" ridge, is an elongated, positive structure deforming the pre-Tertiary basement. The western sector of the Gondola ridge belongs to a major E-W strike-slip lineament extending on land in the Gargano promontory. In the eastern part of the area in question some tectonic features, resembling "pop up"-like and thrust antiforms, are arranged along an arcuate pattern named here "Grifone" trend. The Grifone trend structures indicate a post-Pliocene tectonism probably related to the late stages of the Dinaric-Hellenic orogenesis. The recent westward migration of the Hellenic fold and thrust belt can be demonstrated by the South Adriatic foredeep shift during the last 5-6 million years.

Vengono presentati i risultati preliminari di uno studio sulla stratigrafia e le strutture dell'offshore pugliese tra il promontorio del Gargano e la città di Brindisi (Adriatico meridionale). L'area indagata include vari domini geodinamici: parte dell'avampaese appenninico (Piattaforma Apula Auct.), costituito prevalentemente da carbonati mesozoici di mare basso e parte dell'avanfossa dinarico-ellenica dell'Adriatico meridionale, dove è documentata la presenza di una serie clastica di età neogenico-quaternaria che ricopre un substrato mesozoico-paleogenico costituito prevalentemente da carbonati e marne in facies pelagica.

We propose a processing workflow to enhance the information content of aeromagnetic data. Our workflow is based on the downward continuation and subsequent L-transform of magnetic data. This workflow returns a map showing single highs, which correspond to the location of magnetic bodies, and does not need any a priori information about the source magnetization. We validated our workflow using the aeromagnetic anomalies of the Tyrrhenian Sea (Italy), by a comparison of the reprocessed aeromagnetic anomalies with high-resolution shipborne magnetic data in three selected areas. Through this comparison, we show that the proposed processing workflow of aeromagnetic data leads to more accurate interpretative results. Our results indicate that, in areas where higher resolution data are lacking, the reprocessing of aeromagnetic data according to our workflow may be as decisive as to suggest changes to their previous interpretations or, at least, useful for highlighting areas of special interest, deserving to be magnetically explored by a dedicated high-resolution shipborne survey.