メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.4062500 45.0833333, 142.4125000 45.0833333, 142.4125000 45.0875000, 142.4062500 45.0875000, 142.4062500 45.0833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral