Many parts of such a geologically dynamic continent had evolved during the Quaternary from tectonic and volcanic processes that created significant changes in the landscape, mainly affecting the Andean region. Although the most conspicuous dynamic processes in the Andes were glacial, physical weathering and mass transports have been very important.

     The highlands are presently dominated by geomorphological processes related to climatic regimes ranging from humid tropical to periglacial. During the Quaternary, changes in the character and or the intensity of denudation processes produced mainly extended planation surfaces and associated deposits.

     The major alluvial basins (Amazon, Orinoco, and Paraná) mostly lie under warm humid/subhumid climates. Their fluvial landforms represent important information about the nature of environmental changes in tropical latitudes. Large areas of their river basins (the Orinoco Llanos, the Pantanal, the Pampa and Chaco plains and the Bananal plain) and extensive parts of Patagonian plains contain important sand dunes fields and many deflation hollows. A large part of the Chaco-Pampa plain is covered with loessic materials. Then, the main components of the Quaternary Geology in the lowlands are alluvial megafans, loess-paleosol sequences, dune fields, extensive wetlands and lacustrine sequences. The arid and semi-arid regions contain also evidence of the existence of Quaternary lakes of great importance (the Altiplano/ Puna plateau and Patagonia).

     Quaternary landforms marking different palaeoshorelines reflects the interplay between the different heights of global seal level and the nature and rate of vertical movements in the coastal zone (the elevated marine terraces of the Caribbean coast, the marine terraces of the Atlantic coast and the Amazon and Parana deltas, the elevated terraces of the Chilean and Peruvian Pacific coast, and the submerged quaternary shorelines of the Argentine shelf).