メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.3937500 40.5000000, 141.4000000 40.5000000, 141.4000000 40.5041667, 141.3937500 40.5041667, 141.3937500 40.5000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral