メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.8625000 37.2666667, 138.8687500 37.2666667, 138.8687500 37.2708334, 138.8625000 37.2708334, 138.8625000 37.2666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral