The past decade has witnessed spectacular progress in the collection of observational data and their interpretation in the Pannonian Basin and the surrounding Alpine, Carpathian and Dinaric mountain belts. A major driving force behind this progress was the PANCARDI project of the EUROPROBE programme. The paper reviews tectonic processes, structural styles, stratigraphic records and geochemical data for volcanic rocks. Structural and seismic sections of different scales, seismic tomography and magnetotelluric, gravity and geothermal data are also used to determine the deformational styles, and to compile new crustal and lithospheric thickness maps of the Pannonian Basin and the surrounding fold-and-thrust belts. The Pannonian Basin is superimposed on former Alpine terranes. Its formation is a result of extensional collapse of the overthickened Alpine orogenic wedge during orogen-parallel extrusion towards a 'free boundary' offered by the roll-back of the subducting Carpathian slab. As a conclusion, continental collision and back-arc basin evolution is discussed as a single, complex dynamic process, with minimization of the potential and deformational energy as the driving principle.

The structure of the Pannonian basin is the result of distinct modes of Mid-Late Miocene extension exerting a profound effect on the lithospheric configuration, which continues even today. As the first manifestation of extensional collapse, large magnitude, metamorphic core complex style extension took place at the beginning of the Mid-Miocene in certain parts of the basin. Extrapolation of the present-day high heat flow in the basin, corrected for the blanketing effect of the basin fill, indicates a hot and thin lithosphere at the onset of extension. This initial condition, combined with the relatively thick crust inherited from earlier Alpine compressional episodes, appears to be responsible for the core complex type extension at the beginning of the syn-rift period. This type of extension is well documented in the northwestern Pannonian basin. Newly obtained deep reflection seismic and fission-track data integrated with well data from the southeastern part of the basin suggests that it developed in a similar fashion. Shortly after the initial period, the style of syn-rift extension changed to a wide-rift style, covering an area of much larger geographic extent. The associated normal faults revealed by industry reflection seismic data tend to dominate within the upper crust, obscuring pre-existing structures. However, several deep seismic profiles, constrained by gravity and geothermal modeling, image the entire lithosphere beneath the basin. It is the Mid-Miocene synrift extension which is still reflected in the structure of the Pannonian lithosphere, on the scale of the whole basin system. The gradually diminishing extension during the Late Miocene/Pliocene could not advance to the localization of extension into narrow rift zones in the Pannonian region, except some deep subbasins such as the Makó/Békés and Danube basins. These basins are underlain coincidently by anomalously thin crust (22–25 km) and lithosphere (45–60 km). Significant departures (up to 130 mW m −2 ) from the average present-day surface heat flow ( c. 90 mW m −2 ) and intensive Pliocene alkaline magmatism are also regarded as evidence for the initiation of two newly defined narrow rift zones (Tisza and Duna) in the Pannonian basin system. However, both of these narrow rifts failed since the final docking of the Eastern Carpathians onto the European foreland excluded any further extension of the back-arc region.

The Moroccan salt basin appears to be very unique in the sense that it is not sedimentary loading but tectonic inversion which appears to drive the latest stages of salt-related deformation in the central part of the basin. The gravity potential to maintain salt tectonics is provided by the differential uplift of the Atlas Mountains, located adjacent and striking almost perpendicular to the margin.Along the offshore part of the Moroccan salt basin there are many play types, most of them related to the Triassic syn-rift salt. Toe-thrust anticlines at the basinwards edge of the salt basin form very large structures. Traps associated with salt tongues and diapirs define a more ‘classical’ salt-flank play. Numerous salt tongues, sheets and canopy complexes provide for a ‘Gulf of Mexico-style’ subsalt play. Despite the numerous untested play types, there have been only four deep-water exploration wells drilled in the entire Moroccan salt basin, none of them having subsalt penetrations.

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Exploration experience gained in specific salt basins of West Africa may not be directly applicable to other salt basins along the entire passive margin. To conduct a comparative structural analysis, regional reflection seismic transects were constructed across the salt basins of Morocco, Senegal, Guinea-Bissau, Equatorial Guinea, Gabon and Angola.Regional-scale similarities of the salt basins include the progressive complication of salt-related structures basinward, the change from an extensional domain on the shelf to a compressional domain on the slope and the presence of a toe-thrust front at the oceanward edge of the basins. Regional-scale differences are partly attributed to the relative stratigraphic position of the salt in relation to the rift history.In the better-known post-rift salt basins of Equatorial Guinea, Gabon, Congo and Angola updip extension is represented by a broad rafted domain balanced by downdip contraction in the form of salt tongues, canopies and a toe-thrust zone. The efficiency of this gravity sliding/spreading across the whole margin is due to the more or less uniform original distribution of Aptian salt in the post-rift succession forming a continuous detachment level.In contrast, the typically uneven original distribution of the Late Triassic and Early Jurassic syn-rift salt in Morocco, Mauritania, Senegal, The Gambia and Guinea-Bissau is due to basement highs separating rift half-grabens and creating a different structural pattern. Individual salt structures, such as pillows and diapirs, originated from isolated patches of the autochthonous salt. In the case of syn-rift salt, updip extension may not always be the ultimate driving force for the contractional salt-deformation downdip.