Geospatial Information Extraction: Querying or Quarrying?

Interoperability within geographic information systems (GIS) is concerned with both data and operations. We focus here on the data aspect, more specifically on the access to multiple, distributed, heterogeneous, and autonomous information sources and on their integration. For this purpose, we need to take into account the special requirements of applications dealing with geospatial data, such as:the vast amounts of data considered;the existence of complex and highly-structured data;the co-existence of many different geographic formats;the increasing trend towards reuse of geographic data all over the world;the distributed nature of geographic data.