This paper begins by the statement of some points of divergence with founding texts by French geographers on globalization, particularly about the nature, length and periodization of this process. From a definition of globalization as a geohistorical process of which modernity and capitalism are the main agents, I support against most of these geographies of globalization the thesis of World's homogenization in spite of its growing economic inequality. This argument is grounded on two notions whose presentation is the main objective of this paper, those of "geographic opening" and "geographic globalization" of the various regions of the Earth. Their connection to the World System and the diffusion of modern geographies during the historical periods of the globalization process actually entail an erosion of Earth's diversity or "geodiversity". Examples of these notions are given in the last part of this paper through a short description of the four periods of the geographic globalization, from the XV th century to the present. The conclusion sets out the question of the Earth as ecumene threatened by globalization.