メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.0750000 35.2875000, 137.0812500 35.2875000, 137.0812500 35.2916667, 137.0750000 35.2916667, 137.0750000 35.2875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral