Abstract Ben Peach and John Horne contributed to a revolution in the visualization of stratigraphy and structures using geological maps and cross-sections. In the century since their pioneering fieldwork, the analysis of map structures and the restoration of folds and faults in cross-sections have played a key role in enabling generations of structural geologists to develop theories of displacement and deformation in orogenic belts. However, classical printed maps have practical limitations. They are often inaccessible, they may be difficult to interpret and they are expensive to update when errors or new data come to light. Today, a new wave of the geological mapping revolution is in progress thanks to interactive geo-browsers such as Google Earth, which are opening up possibilities for tectonic visualization that were inconceivable only a decade ago. We discuss the digital deconstruction of classical geological maps of the British Isles and Ireland, such as those by William Smith, Sir Archibald Geikie, Ben Peach & John Horne, and others, and we demonstrate how Google Earth and Google SketchUp can turn the digitized versions of these maps into truly four-dimensional spatio-temporal visualizations.

Abstract Metamorphic and plutonic basement rocks and cover sequences of the Eastern Sierras Pampeanas, Argentina, have undergone multiple episodes of fault reactivation. Faults take advantage of mid- to late Cambrian, NW-SE-striking, steeply east-dipping foliations in Vendian-aged accretionary prism metasedimentary rocks. Foliations in peraluminous schists, paragneisses and migmatites are deflected into late Cambrian amphibolite-grade high-strain zones. Greenschist-grade mylonite zones and thick retrogressed ultramylonite zones with mainly NNW strikes, easterly dips, and east-over-west movement, affect the metasedimentary rocks and Ordovician-aged intrusive rocks and are presumably related to early Devonian accretion of terranes to the west of Gondwana. pseudotachylyte veins occur in nearly all mylonite zones. Brittle deformation during Carboniferous to Triassic time produced major pull-apart basins located above terrane boundaries. Outcrop patterns of Triassic to Cretaceous sedimentary rocks are consistent with transtensional pull-apart basins followed by Andean transpressional deformation. The theoretical basis for fault reactivation and production of ‘short cuts’ is examined in the context of Tertiary to Recent basin inversion faults. The inversion faults follow the Palaeozoic trends and produce the present-day NNW-oriented, deep sedimentary basins and intervening ranges of basement rocks.