メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.1187500 36.5333333, 138.1250000 36.5333333, 138.1250000 36.5375000, 138.1187500 36.5375000, 138.1187500 36.5333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral