メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.9187500 38.7791667, 139.9250000 38.7791667, 139.9250000 38.7833333, 139.9187500 38.7833333, 139.9187500 38.7791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral