メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.1500000 45.1541667, 141.1562500 45.1541667, 141.1562500 45.1583333, 141.1500000 45.1583333, 141.1500000 45.1541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral