Abstract : Taking geodiversity to be a geographical interpretation of the spatial diversity of the Earth's surface, it can be defined as the morphologic diversity of 'natural environments' ('milieux naturels'), or alternatively as the diversity of landscapes, when considered as a physical landscape. In an effort to contribute to a more coherent body of theory and a multilingual and pluricultural approach to geodiversity, this work situates itself within the field of fundamental geographical research. It highlights and differentiates between the notions of geodiversity and landscape diversity, whilst using an empirical method to deal with a central question; 'How can geodiversity be measured ?', if it is interpreted as 'mesologic diversity' and 'diversité paysagique' (describing the diversity of physical structures within the landscape), taking into account the lateral and vertical structures of spatial diversity. A clear distinction should be made between general geodiversity, and geological diversity. Indeed, a general definition of geodiversity takes into account biotic as well as abiotic elements. It also encompasses the human effect on these environments, without making a distinction between minerals and living things, or between artificial and natural elements. A systemic approach might suggest that spatial structures; the morphology of the environment, reflect their processes and dynamics. In employing an integrated approach to these 'natural environments' whilst also consulting floristic and soil samples, it has been shown that diversity is organised on many levels.The empirical section of the work uses a multiscalar approach to exploring the geodiversity of the 'Massif du Madres - Coronat', which is situated in the Franco-Catalonian region of the Eastern Pyrenees. At the Site of Community Importance - the 'Massif du Madres - Coronat', the broad diversity of 'natural environments' is characterised by specific varieties of rock, topography, levels of vegetation and differentiated land use. Samples and observations taken from the study site have made it possible to bring mesologic diversity to the fore, and to study the relationship between geodiversity and phtyodiversity. A cartographic study of 'géons' (a spatial landscape unit) using remote sensing, illustrates the land mosaics - a range of lateral structures that represent the physical diversity of the landscapes ('diversité paysagique'). When used in conjunction with the data, diversity metrics and multivariate statistics contribute to understanding the character of the site's geodiversity. This has demonstrated a relatively high level of mesologic diversity in types of forests and shrubland, and an increased level of 'diversité paysagique' in elevated areaswhich have been shaped by Quaternary glaciation, and in areas close to talwegs. The results of this analysis form the basis of a discussion concerning the properties and useful potential of geodiversity within the framework of managing the landscape and protected areas.