メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.4500000 40.6125000, 141.4562500 40.6125000, 141.4562500 40.6166667, 141.4500000 40.6166667, 141.4500000 40.6125000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral