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The restoration of structures along balanced cross sections through the West Carpathian accretionary wedge and pseudo-3D restoration in the Smilno Tectonic Window area shows that various defined units contain sediments from Magura and Silesian depositional areas. The shortened Magura succession was detached at the Upper Cretaceous stratigraphic level. The shortened Silesian sedimentary package was detached at the Lower Cretaceous stratigraphic level. The Magura succession was the southwestern neighbor of the Silesian succession in a large depositional system. Both sedimentary packages were shortened during the Paleogene and the Magura succession was later thrust over the Silesian succession as an out-of sequence oblique thrust during the Neogene. The general shortening mode is piggy-back. Thrust geometries are created by both fault-bend and fault-propagation folding. The common out-of-sequence thrusting is caused by the involvement of the basement in the shortening and by interplay of friction and erosion. The influence of basal friction on thrust sheet length is validated by sand-box models. Variations in friction along the basal thrust include low friction, documented by subhorizontal veins with vertically grown fibers and long thrust sheets, medium friction, indicated by duplexing and high friction, indicated by antiformal stacks and back thrusting.

Four profiles across the obliquely convergent West Carpathian external zone, together with a field study of the area, indicate the interrelation of thrusting and strike-slip faulting in the transpressionally deformed wedge. In the front of the wedge, thrusting is dominant. Towards the hinterland a progressively greater proportion of strike-slip faulting is found. The resultant deformational paths are curvilinear, diverging from the parallel with the northeast-vergent orogen advance. The external zone of the West Carpathian arc consists of two parts: first, a zone of frontal compression perpendicular to the orogen advance vector; and second, a zone of lateral sinistral transpression, which is at a lower angle to the orogen advance vector. The displacement along correlated strike-slip faults progressively decreases towards the zone of frontal compression.

This paper describes palaeostresses calculated from fault-striae data, the inferred palaeostrain patterns and determines the inter-relation of the compression and extension during the Tertiary development of the West Carpathians. The calculated stress and inferred strain patterns for the Palaeogene–Burdigalian indicate that the ancestral West Carpathians formed a more-or-less straight orogenic belt. This belt underwent contraction and uplift in its narrow frontal zone, stretching along its strike during the Paleocene–Chattian, and regional contraction and uplift during the Chattian–Burdigalian. The strain/stress pattern is similar to the collision-related pattern known from the Eastern Alps for the Paleocene–Burdigalian. During the Burdigalian–Tortonian, the calculated and inferred West Carpathian stress and strain patterns indicate narrow frontal contractional and lateral sinistral transpressional zones in the orogenic front and broad extensional and dextral transtensional zones in the orogenic interior. The stress/strain pattern is similar to the subduction-related pattern known from areas such as the Hellenic or Sunda/Banda Arcs.

The tectonostratigraphic analysis presented here aims to establish a broad stratigraphic framework within which the likely distribution of both reservoir and source rock intervals within the deep-water Voering and More basins can be evaluated. In terms of hydrocarbon potential, the Devonian to Triassic interval can be effectively discounted by its extreme depth of burial across most of the study area. The Middle Jurassic is interpreted to provide a potential reservoir target in the Gjallar Ridge area. The Cretaceous is seismically mappable across the region and has been divided into five tectonostratigraphic sequences. Late Cretaceous reservoirs are considered to offer targets in the Nyk High area. Six tectonostratigraphic sequences are described within the Cenozoic succession. Paleocene reservoirs are interpreted to offer targets over both the Ytterskallen and Ormen Lange areas of the More Basin. Source rock maturity is critical for exploration success. Mapping shows the Late Jurassic/earliest Cretaceous Spekk Formation to be overmature over most of the area, though the presence of possible DHIs indicates the probable presence of major gas accumulations in the region. Only on the western flank of the Vigrid Syncline does the Spekk shallow sufficiently to lie within the potential oil window. It is concluded that the region has the potential to become a significant new hydrocarbon province for the 21st century.

The Limpopo Orogeny, which lasted from ∼ 2700 to ∼ 2600 Ma, was characterised by NNW-SSE directed shortening. This resulted in both crustal thickening, accommodated by folding and NNW-directed thrusting, and associated crustal extrusion whereby a number of crustal blocks, including the Central Zone of the Limpopo Belt, was displaced to the west-southwest along WSW-ENE trending shear zones. This was part of a regionally distributed phase of orogenic deformation which affected the adjoining Kaapvaal and Zimbabwe Cratons from the Witwatersrand Basin in the south to the Harare Greenstone Belt in the north. This deformation, which migrated northwards with time, postdated an earlier phase of crustal accretion during which the Archaean crustal unit now marked by the Kaapvaal and Zimbabwe Cratons and the Limpopo Belt, grew towards the north-northwest. Shortening of this unit during the Limpopo Orogeny may be regarded as the last stage of the crustal accretion process. This tectonic process of continental growth by accretion followed by crustal shortening with associated crustal extrusion has many features in common with Tibetan tectonics from the Mesozoic to the present.

Sea-floor palaeomagnetic data that reflect variations in rate and vector of Indian Plate movement and rotation suggest that initial collision between India and Asia occurred at about 50–55 Ma ago. As the pre-collisional Indian Plate was diamond shaped, with the northern margin comprised of two oblique boundaries, collision was earliest where these boundaries meet, or in what is now the northwest Himalaya. Oblique convergence along each of these two boundaries would generate rotation of thrust sheets as they climb on to the Indian Plate. The oroclinal shape of the main Himalayan chain to the east of the northwest Himalayan syntaxes reflects a combination of the effects of oblique convergence, post-collisional anticlockwise rotation of the Indian Plate, and the pinning of the main thrusts at their northwestern terminations by crust thickened during the earliest collisional stage. The Indian Plate rotation enhances a strike-slip component of movement along the western oblique margin, with the transpressively sinistral Chaman fault zone now acting as a continental escape structure.

The northern part of the Indian Plate in North Pakistan is composed of a number of large-scale crustal nappes, each of which are stratigraphically distinct, and which were stacked late in the main phase of southeasterly directed thrusting associated with the Himalayan event. The major nappes recognised in the Swat to Kaghan area of North Pakistan are the Besham, Swat, Hazara, Banna, Lower Kaghan and Upper Kaghan nappes. Metamorphism was synchronous with early stages of deformation. Within each nappe the metamorphic grade increases upwards, an overall inversion that represents post-metamorphic imbrication within individual nappes, synchronous with the main phase of nappe stacking, rather than a “hot iron” type inversion as described under the MCT in Nepal and India. As a result of this “within-nappe” imbrication each thrust slice within any particular nappe contains rocks of a higher metamorphic grade than those in the slice below, with sharp metamorphic breaks across the imbricating thrusts as well as across the major shears that bound the crustal-scale nappes. Uplift along these imbricating thrusts initiated cooling of the stack. K-Ar mica and hornblende cooling ages imply that much of this uplift was completed by 30 Ma, or within 20 Ma of the collision.