Data model geology - the structure for geological data sets in Switzerland
|Location||International Geological Congress,oslo 2008|
|Author||Oesterling, Nils; Baland Renaud, Pauline; Kuehni, Andreas|
|Holding Date||29 September 2008|
Digital geological data are becoming increasingly important in recent years in Switzerland. This increase is largely due to the growing number of natural hazards. Events such as the flooding of various Swiss rivers in the summer of 2005 and the rock fall directly striking a car on the Gotthard Highway in 2006 make the preparation of natural hazard maps indispensable. An important basis for this kind of map is geological information, especially in digital form.
The Swiss Geological Survey (SGS) is responsible for geological mapping in Switzerland and supplies basic geological geo-information. Various map series and data sets are available in printed and digital raster formats. However, the availability of vector data sets is strongly limited for the following reasons:
1. Although the number of vectorised data sets is continuously increasing (cf. Baland Renaud et. al., this abstract volume), only a small amount of them presently exist.
2. The structure (i.e. attribute tables and values, etc.) of the existing vector data sets is non-uniform and varies among individual data sets.
To be able to supply consistently structured, seamless geological data sets for all of Switzerland, the SGS is developing a conceptual data model for the geology of Switzerland. This model is divided into two parts:
1) Data storage: Definition of thematic groups (themes) and sub-groups (classes) representing geological object types and its internal structure. Nine themes are distinguished, each of which have one to eleven classes. A total of about 50 classes containing more than 200 object types are currently defined. The number of thematic groups is not restricted, allowing geo-information from other disciplines (e.g. hydrogeology, geophysics, etc.) to be integrated into the model.
2) Look-up tables: Definition of the structure of semantic information (attributes). The definition of standard attribute values is part of a separate project, which will begin in the near future.
Part one of the data model is now finished and will be tested on a restricted number of data sets. Part two is currently in preparation and will be completed at the end of 2008.
For the development of the model UML and INTERLIS are used. INTERLIS is a Swiss standard modelling language, which was originally introduced for exchanging data from cadastral surveying. Such data modelling is required because geological information is defined as basic geo-information in the Swiss national spatial data infrastructure (NSDI), which demands usage of the above mentioned languages.
Upon completion of the data model, the geological data in Switzerland can be structured consistently, and seamless vectorised data sets of the entire country can be prepared and supplied to the geoscientific community for fulfilling their respective tasks. Data supply will be ensured in a conventional style (CD, FTP, etc.) or by setting up Web Services (OGC WMS, WFS, etc.).