メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.1125000 38.4333333, 141.1187500 38.4333333, 141.1187500 38.4375000, 141.1125000 38.4375000, 141.1125000 38.4333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral