メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.1500000 34.1000000, 131.1562500 34.1000000, 131.1562500 34.1041667, 131.1500000 34.1041667, 131.1500000 34.1000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral