U.S. Department of the Interior U.S. Geological Survey Geospatial Semantic Vocabulary for The National Map Dalia Varanka, Lynn Usery, and David Mattli GeoVoCamp Washington D.C. June 3-4, 2011

Some Challenges  Great many types of topographic features  Sets of spatial relation terms and logical axioms for topographic features do not exist  The vocabulary must serve a wide range of expert and non-expert users

Parameters for Topographic Terms  Topography means the observation and experience of the landscape environment within a proximity  Topographic data represents natural and built features on the surface of the earth  Easily learned basic feature  Features that don’t require a lot of abstract thinking  Scientific applications

Example Query  General Query: Find all other features that cross a given feature  Specific Example: Find all tributaries of West Hunter Creek from the The National Map

Data Conversion  Automated conversion of sample data from The National Map reuses feature codes from digital GIS data models

Topography Semantics  5.owl/.n3 files by themes Each term includes: Definition On-line source Plain English label URI (start of) Axiom list

Open Geospatial Consortium Draft GeoSPARQL Specification  OGC Simple Features standard spatial relations based on M. Egenhofer 9-intersection model Simple FeaturesRCC8Egenhofer equalsEQequal disjointDCdisjoint intersects¬ DC¬ disjoint touchesECmeet withinNTPP + TPPinside + coveredBy containsNTPPi + TPPicontains + covers overlapsoverlap

Topological Relations  Regional Connection Calculus: relations based on interior, boundary, and exterior contact between two features *disconnected (DC) *externally connected (EC) *equal (EQ) *partially overlapping (PO) *tangential proper part (TPP) *tangential proper part inverse (TPPi) *non-tangential proper part (NTPP) *non-tangential proper part inverse (NTPPi)

Topographic Spatial Relations  Relations from USGS/partner standards FLOW WaterflowTHROUGHArroyo (Watercourse or channel) waterflowTHROUGH Channel (Linear deep part of a body of water) Underground waterflowTOThe surface of the Earth CAUSED Crater (Circular-shaped depression at the summit of a volcanic cone or one on the surface of the land) causedBYthe impact of a meteorite Crater (a manmade depression)causedBYan explosion FORM Crossing (A place where two or more routes of transportation) form a junction or intersection (overpass, underpass) REMOVED Mine (place where commercial minerals) removedFROMEarth Oilfield (area where petroleum is/was) removedFROMEarth

Spatial Analysis of Relations  For any given feature,  Cartographic ‘thumbprint’ of 3 real-world examples  List relations and observations  Compare with verb/preposition pairs  Compile for spatial relation vocabulary

Hypothesis  Topological relations (GeoSPARQL)  Mereological (part-whole) relations .owl, skos extensions, and others  Study of spatial cognition embedded in prepositions and their match to spatial relation operators