Abstract In March 1833 Charles Darwin discovered Devonian fossils in the Falkland Islands. He was excited by his find but could have had little premonition of the long-running geological controversy that he was initiating. Darwin's fossils matched a coeval South African fauna and, as further collections were made, the association was apparently strengthened. A particularly important contribution arose around 1910 through collaborations between a local collector, Constance Allardyce, and professional palaeontologists: Ernest Schwarz in South Africa and John Clarke in the USA. The accumulating evidence was seized upon by the early proponents of ‘displacement theory’ – continental drift – notably Alexander Du Toit, who relocated the Falkland Islands northward for his 1927 South Atlantic reconstruction. A more radical, but geologically sounder proposal arose in 1952 when Ray Adie suggested that the Falkland Islands, rotated through 180°, had originated as the eastward culmination of the Cape Fold Belt and Karoo Basin. In effect, Adie had presciently described a rotated microplate, perhaps the first on record. An opposing view saw the Falkland Islands as part of a fixed, South American promontory, and argument around these two contrasting interpretations of South Atlantic geology continues to the present day.

Abstract Orientated carbonate (calcite twinning strains; n = 78 with 2414 twin measurements) and quartzites (finite strains; n = 15) were collected around Gondwana to study the deformational history associated with the amalgamation of the supercontinent. The Buzios orogen (545–500 Ma), within interior Gondwana, records the high-grade collisional orogen between the São Francisco Craton (Brazil) and the Congo–Angola Craton (Angola and Namibia), and twinning strains in calc-silicates record a SE–NW shortening fabric parallel to the thrust transport. Along Gondwana's southern margin, the Saldanian–Ross–Delamerian orogen (590–480 Ma) is marked by a regional unconformity that cuts into deformed Neoproterozoic–Ordovician sedimentary rocks and associated intrusions. Cambrian carbonate is preserved in the central part of the southern Gondwana margin, namely in the Kango Inlier of the Cape Fold Belt and the Ellsworth, Pensacola and Transantarctic mountains. Paleozoic carbonate is not preserved in the Ventana Mountains in Argentina, in the Falkland Islands/Islas Malvinas or in Tasmania. Twinning strains in these Cambrian carbonate strata and synorogenic veins record a complex, overprinted deformation history with no stable foreland strain reference. The Kurgiakh orogen (490 Ma) along Gondwana's northern margin is also defined by a regional Ordovician unconformity throughout the Himalaya; these rocks record a mix of layer-parallel and layer-normal twinning strains with a likely Himalayan (40 Ma) strain overprint and no autochthonous foreland strain site. Conversely, the Gondwanide orogen (250 Ma) along Gondwana's southern margin has three foreland (autochthonous) sites for comparison with 59 allochthonous thrust-belt strain analyses. From west to east, these include: finite strains from Devonian quartzite preserve a layer-parallel shortening (LPS) strain rotated clockwise in the Ventana Mountains of Argentina; frontal (calcite twins) and internal (quartzite strains) samples in the Cape Fold Belt preserve a LPS fabric that is rotated clockwise from the autochthonous north–south horizontal shortening in the foreland strain site; Falkland Devonian quartzite shows the same clockwise rotation of the LPS fabric; and Permian limestone and veins in Tasmania record a thrust transport-parallel LPS fabric. Early amalgamation of Gondwana (Ordovician) is preserved by local layer-parallel and layer-normal strain without evidence of far-field deformation, whereas the Gondwanide orogen (Permian) is dominated by layer-parallel shortening, locally rotated by dextral shear along the margin, that propagated across the supercontinent.

Abstract This work presents research that we intended to publish jointly with Maarten de Wit on the importance of Hans Keidel in the definition of the Gondwanides and in his pioneering proposal of correlation between the Sierras de la Ventana mountain system in the province of Buenos Aires, Argentina, and its counterpart in the Cape System in South Africa. Keidel's proposals were used by Wegener in the 1920 second edition of his ‘Theory on Continental Drift’. Keidel's role and his ideas of correlation were recognized and strengthened by du Toit's fieldwork in 1923 in the Sierras de la Ventana and which he left behind in his field notebook. Du Toit has the credit of being the first to carry out fieldwork on both continents. His observations and his precise correlations confirmed Keidel's hypotheses through his 1927 publication and his book on the Wandering Continents. It is noteworthy that after Wegener's death in 1930, du Toit defended the Theory of Continental Drift for years almost alone. The work is documented with photographs from du Toit's trip to South America, the originals of which have been lost in the devastating 2021 fire at the Jagger Library at the University of Cape Town.

Abstract The Pennsylvanian on the western rim of Gondwana can be considered a time of significant contrasts in terms of environments, revealing a unique translatitudinal disposition of the South American continent, where glaciomarine deposits and peat-forming environments, situated further south, coexisted with marine carbonate platforms and aeolian dune fields, in terrains further north. This peculiar record creates an opportunity to better understand the teleconnections of glaciation and deglaciation during the Late Paleozoic Ice Age (LPIA) between mid and low latitude regions. In the last decade, radiometric dating together with marine microfossils (mostly conodonts) has enabled a better understanding of the timing and duration of deposition of different sedimentary environments found in the climate belts that originated from a global ice-house regime. These advances in the chronostratigraphical positioning of sedimentary deposits also allow a more precise correlation between them, making it possible to estimate cause–effect patterns arising from the growth and decay of glaciers in this portion of Gondwana. This contribution aims to present an overview of the main climatic–environmental events that took place during the Pennsylvanian and to associate them with the floristic changes that occurred in the emergent lands based on palaeobotanic and palynological information. The record from the west rim of Gondwana could be roughly divided into Early, Middle and Late Pennsylvanian, exactly as proposed in the geological time-scale.