メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.3625000 44.2583333, 145.3687500 44.2583333, 145.3687500 44.2625000, 145.3625000 44.2625000, 145.3625000 44.2583333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral