The application of geography markup language (GML) to the geological sciences

Abstract

GML 3.0 became an adopted specification of the Open Geospatial Consortium (OGC) in January 2003, and is rapidly emerging as the world standard for the encoding, transport and storage of all forms of geographic information. This paper looks at the application of GML to one of the more challenging areas of automated geography, namely the geological sciences. Specific features of GML of interest to geologists are discussed and then illustrated through a series of geological case studies. We conclude the paper with a discussion of anticipated geological web services that GML will enable. GML is written in XML and makes use of XML Schema for extensibility. It can be used both to represent or model geographic objects and to transport them across the Internet. In this way it serves as the foundation for all manner of geographic web services. Unlike vertical application grammars such as LandXML, GML was intended to define geographic application languages, and hence is applicable to any geographic domain including forestry, environmental sciences, geology and oceanography. This paper provides a review of the basic features of GML that are fundamental to the geological sciences including geometry, coverages, observations, reference systems and temporality. These constructs are then employed in a series of simple geological case studies including structural geological description, surficial geology, representation of geological time scales, mineral occurrences, geohazards and geochemical reconnaissance.