1. GML encoding of NADM C1 Connecting geosciences to international standards Eric Boisvert (GSC) Bruce R. Johnson (USGS) Boyan Brodaric (GSC) Simon Cox (CSIRO)

2. What is GML ? Geography Markup Language XML encoding of ISO standard for representation of geographic features Building blocks, providing… Feature model Points, lines, polygons (geometries) Projection definitions Dictionary structures Topology, Temporal, and more..

3. What is GML? GML by itself has little use Need to define a GML application Extend the provided building blocks and assign domain (community) specific meaning. gml:_GML gml:_Feature gml:_GML gml:_Geometry gml:_PropertyValue Street

4. Why GML ? International standard (Open GIS Consortium) Opens the possibility to connect to other standards WFS (Web Feature Service) Can be used with GML enabled tools

5. Why GML ? GML client NADM-GML USGS WFS GSC Etc. WFS internet USGS schema GSC schema other schema internet

6. GML is XML Uses XML to define the building blocks Defined with standard XML schema We use XML schema to extend GML Constraints and restrictions defined the same way any other XML schemas are GML document must validate against a XML schema (GML schema + domain specific schema)

7. GML is not any XML GML has rules (conceptual model) Features must derives from core GML features GML also has syntax rules Class->property->Class->property Mandatory ids Provides ‘design patterns’

8. Example Handbury Road North 1 2 2 3 3 4 4 0 2 Asphalt Mandatory ID properties Features have 0 or more geometries RoadSegment -name: string -numberOfLane: int -surfaceType: string gml:_GML gml:_Geometry 0..* +centerLineOf

9. Example Handbury Road North 2 Asphalt … 1 2 2 3 3 4 4 0

10. Encoding NADM C1 Start from conceptual model Must create a GML friendly implementation model Turn association classes into ‘bridge’ class Define who contains who Define properties and name them

11. {Must be part of current CM} _CompoundMaterial -consolidationDegree: string MineralOrganicMaterialVoid InorganicFluid Rock UnconsolidatedMaterial Glass EMConstituent -proportion: double -emcRole: string GeologicRelation 0..1 +emFabric 0..* 1 11 +emConstituentMaterial 1..* +emConstituentProperty 1 _GeologicFeature _EarthMaterial -metamorphicGrade: string -color: string 0..* +emcRelation Conceptual GML Friendly Fabric -pervasiveness: string

12. _GeologicFeature _EarthMaterial -metamorphicGrade: string -color: string 0..* _CompoundMaterial -consolidationDegree: string 0..1 +emFabric Fabric -pervasiveness: string Rock _GeologicEvent Genesis 0..1+emGenesis 0..* EMConstituent -proportion: double -emcRole: string +emConstituentProperty 1..* 1 +emConstituentMaterial

13. International effort GML encoding is done within an international effort to improve interoperability of geoscience First meeting in Edinburgh (Nov. 2003) Next meeting Florence (August 2004) Testbed planned