It has been shown in the accompanying paper that the Sub-Andean foreland can be subdivided longitudinally into a number of tectonostratigraphic domains. To test the hypothesis that changes in palaeodepositional setting rely on the presence of a series of transverse zones of structural accommodation, data have been digitally compiled from across the South American continent. Spatial and temporal geological relationships have been analysed and evaluated as a means of identifying the position of tectonostratigraphic domain boundaries (structural accommodation zones), and patterns of subsidence and intraplate deformation. The results suggest that individually these structural accommodation zones represent a composite of deep crustal fractures which, on a regional scale, interlink to form a transcontinental belt or zone that can accommodate intraplate deformation during episodes of plate reorganization. Their strong spatial relationship with Mesozoic, intraplate, alkaline igneous activity suggests that they exerted an important control on lithospheric melt siting during Gondwana breakup. These localized zones of high heat flow have important implications for source rock maturity in the interior, Phanerozoic intracratonic basins of South America. On the South Atlantic margin, the majority of these crustal lineaments correlate with failed arms of triple-junction rifts and define the boundaries to tectonostratigraphic domains recognized along the South Atlantic Rift System.

Within the SW Grampian Highlands several NE–SW-trending shear zones and faults related to the Caledonian transpressional collision are recognized as being distinct from an intersect­ing set of NW–SE-trending pre-Caledonian crustal lineaments which were reactivated during Caledonian orogenesis. The geochemical and isotopic characteristics of the 425–400 Ma granitoids of this region show that they were derived by anatexis of the lower crust associated with a mantle component which provided an influx of mantle heat and/or metasomatic fluids; their spatial distribution suggests a close genetic relationship with Caledonian shear zones. Having made the fundamental distinction between ascent (transport) and emplacement (arrival) configurations possible for granitoid magmas, new data are presented for these plutons which show that: (i) a common modal sequence of intrusive phases can be recognized; (ii) these phases are all sited at shear zone or lineament intersections where transtensional zones allowed and facilitated ascent; (iii) emplacement was often by a process of localized in situ ballooning. The existence of such lineaments in these orientations in the SW Highlands may indicate that the structure of the lower crust can be regarded as a series of blocks bounded by intersecting ductile zones of high strain. The establishment of such a pattern of structural interactions within the lower crust could provide a mechanistic framework within which the location of anatectic zones, siting and ascent pathways and any subsequent emplacement phenomena can be explained in orogenic belts.

The tectonic, structural and depositional history of 19 Sub-Andean foreland and eight southern Caribbean basins has been synthesized and is summarized by regional geohistory charts. These charts recapitulate the subsidence regimes recognized and have been used to evaluate correlations between genetically related stratigraphic sequences. Based on spatial and temporal changes in palaeo-depositional setting, the Sub-Andean region can be subdivided longitudinally into several tectonostratigraphic domains. The differential amount of subsidence between two adjacent tectonostratigraphic provinces or sub-provinces relies on the presence of a transverse zone of structural accommodation. The location of these transfer zones correlates with a number of known and several newly identified zones of intracontinental deformation. Combined with changes in the structural geometry of the Andean Fold and Thrust Belt and the relative dominance of basement fault systems along the length of the Andean foreland, it is suggested that the Andean Belt can be separated into five tectonic domains (which are themselves bounded by transverse, structural accommodation zones). Representing the multiphase reactivation of pre-existing basement fault systems, the influence of these broad zones of transcontinental deformation is most apparent during the Triassic-Jurassic period, suggesting that they were intimately associated with accommodating intraplate stresses during the breakup of the Gondwana Supercontinent.

The Sub-Andean foreland region is summarized in a series of palaeogeographical maps. Various time-slices show important basin-forming processes and the extent and evolution of principal depositional elements. Based on spatial and temporal changes in palaeodepositional setting, the Sub-Andean region can be subdivided longitudinally into a number of tectonostratigraphic domains. The differential amount of subsidence between two adjacent tectonostratigraphic provinces or sub-provinces has been taken up across, complex, broad, transverse, transcontinental accommodation zones, which probably represent the multiphase reactivation of pre-existing fault systems in the underlying basement. Two predominant sets of basement lineaments are recognized: ENE-WSW and NW-SE. Both sets of lineaments occur as major structural anisotropies throughout the basement rocks of South America, providing zones of weakness, which were repeatedly reactivated and, at least in part, controlled: (a) the geometry of inter-and intra-cratonic rifting; (b) rates of subsidence and uplift along the Andean depositional axis; (c) the position of basin-bounding and intra-basinal highs/arches; (d) the structural geometry of the Andean Deformation Zone, correlating with changes in deformational style and major deflections; and (e) the location of magmatism.Based primarily on source rock age, it is suggested that these transverse, structural accommodation zones had a profound effect on source rock distribution and hydrocarbon occurrence; subdividing the Sub-Andean region into five petroleum provinces/megasystems: a 'Northern' Late Cretaceous (La Luna Formation and equivalents); a 'Western' Late Palaeozoic-Early Mesozoic (Permian and Upper Triassic to Lower Jurassic source rocks); a 'Central' Palaeozoic (Late Devonian and Silurian); an 'Eastern' Tertiary; and a 'Southern' Mesozoic.

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