メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.4000000 35.4500000, 139.4062500 35.4500000, 139.4062500 35.4541667, 139.4000000 35.4541667, 139.4000000 35.4500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral