メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.7500000 38.7166667, 139.7562500 38.7166667, 139.7562500 38.7208334, 139.7500000 38.7208334, 139.7500000 38.7166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral