3D and 4D Geomodelling Applied to Mineral Resources Exploration---An Introduction

3D geomodelling, a computer method for modelling and visualizing geological structures in three spatial dimensions, is a common exploration tool used in oil and gas since more than several decades. When adding time, 4D modelling allows reproducing the dynamic evolution of geological structures, and reconstructing the past deformation history of geological formations. 3D geomodelling has been applied to mineral exploration with some success since more than 15 years, but can be considered still challenging for modelling hard rock settings. If very few 4D modelling case studies have been carried out in mineral exploration, it nowadays begins to be applied in structural geology and mineral resources exploration. This paper describes the 3D and 4D geomodelling basic notions, concepts, and methodology when applied to mineral resources assessment and to modelling ore deposits. It draws on the state of the art of 3D and 4D-modelling, describing advanced techniques, limitations and recommendations. The text is illustrated by several 3D GeoModels of mineral belts across Europe, including the Fennoscandian Shield (Finland, Sweden), Hellenic (Greece), Iberian (Spain, Portugal) and Foresuedic (Poland, Germany) belts, all of those case-studies have been performed within the EU FP7 ProMine research project (Part of objectives of the 4 years ProMine project were to integrate the mapping of metal and mineral resources across the European Union, especially in WP1 and WP2). Perspectives and recommendations on applying 3 and 4 geomodelling in mineral resources appraisal are given in the conclusions.