BRAZIL 309 dispersal of western Gondwana A closer examination of the cratons and Neoproterozoic orogenic belts reveals, however, a long and diverse pre-Gondwana history, as well as a whole series of post-Gondwana features Thus, in addition to the Brasiliano and South Atlantic events, other events of the same significance and extent are recorded in different ways in the South American platform and its cover The most important of these events, together with their ages, areas of occurrence, and geotectonic significance, are shown in Table Regional Structures and Topography of Brazil The topography of Brazil to a large extent reflects the constitution of the South American platform discussed in the previous section The cratons underlie the low areas, hosting the main river basins; the highlands, on the other hand, have the Neoproterozoic orogenic domains as their substrata (Figure 4) Each of the large-scale topographical highs and lows of the Brazilian territory is the expression of a particular regional tectonic structure Some of these structures had already nucleated by the Palaeozoic The majority, however, were initiated in the Mesozoic and underwent significant reactivation during the Cenozoic The most prominent structural and topographical lows correspond to the Parana´ , Sa˜ o Francisco, Parnaı´ba, and Amazonas basins The Borborema Plateau, the Serra Mar Uplift, and the Alto Paranaı´ba Arch are the largest structural and topographical highs (Figure 4) Cratons The cratons of the South American platform, consisting of Archaean crust with substantial Figure Correlation between the large scale tectonic structures and the topographical relief of Brazil Relief map compiled by JBL Franc¸olim based on EROS GTOPO 30 dataset; reproduced with the permission of the author