メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.4437500 38.2291667, 139.4500000 38.2291667, 139.4500000 38.2333333, 139.4437500 38.2333333, 139.4437500 38.2291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral