Geological data are used in a variety of applications. These data have three dimensional (3D) nature and hence 3D modeling, storage, dissemination and presentation of the data not only provide a better understanding of the current situation and the relationship between different features and data layers, but also increase the reliability of decisions. 3D Web Geographical Information Systems (3D Web GIS) are proper tools for managing and sharing geological data. However, current activities on developing geological Web GISs have paid less attention on 3D nature of geological data. In other words, most of the existing geological Web GISs are studied or established based on two dimensional data.
One of the important challenges for dissemination of 3D geological data in Web relates to utilization of a proper format for rendering 3D data in Web browsers. Such a format should have the capability of: 1- Conveying geological data, three dimensionally, in Web environment, 2- being displayed by Web browsers, 3- being standard and the standard to be clear for data producers in such a way data conversion to the desired format being possible, 4- conveying attribute data, and 5- providing users with the possibility of querying and analyzing data. Up to the knowledge of the authors, there is not currently any software which can disseminate 3D geological data in Web by employing a proper format respecting all of the above criteria. This paper proposes utilizing X3D, developed by Web 3D Consortium, as a standard text-based format for dissemination and rendering 3D data in Web. Although the format has not been developed for GIS purposes, in this research the applicability of that for modeling and presenting 3D geological data in 3D Web GIS is investigated.