Part I Introduction -- Nature of Work -- Area and Material of Study.-Metodology -- Background -- Part II Results and Discussion -- Chacoparanense Basin and North Margin of the Salado Basin -- Proposed Litostratigraphic Units -- Península de Valdés -- Part III Conclusion. This book gathers and updates the most significant advances of the last two centuries and presents an unprecedented micro paleontological study covering more than 20 stratigraphic sections. This information is supplemented by numerous sedimentological observations and analyses, on the basis of which a new lithostratigraphic framework for the Neogene of the Chacoparanense Basin is proposed. The book is structured in an easy-to-read format: Its main section offers a comprehensive review of the current state of knowledge on transgressions in Argentina and similar transgressions in other South American countries, taking into account various key aspects (age, paleoenvironment, micropaleontology, etc.). Secondly, the book presents the main results on the TLP and TEP of the Chacoparanense Basin and the TEP of the Península de Valdés. Lastly, it provides readers with complete stratigraphic profiles (Appendix A), mineralogical analyses (Appendix B), distribution charts (Appendix C), systematics (Appendix D) and plates (Appendix E).