Introduction.- 1. The Geological Context.- 2. The Paleontological Context Ichnology.- 2.1 Scheme of Continental Ichnofacies.- 2.2. The Ichnological record in the Cenozoic of Pampasia.- 2.3. Insect Nests in Paleosoils.- 3.A. Faunistic Associations and Climatic Events during the Panaraucanian cycle.- B. Faunistic Associations and Climatic Events during the Pan-Pampean cycle.- 4. Conclusions