メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0500000 38.7833333, 141.0562500 38.7833333, 141.0562500 38.7875000, 141.0500000 38.7875000, 141.0500000 38.7833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral