メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.2187500 40.2250000, 141.2250000 40.2250000, 141.2250000 40.2291667, 141.2187500 40.2291667, 141.2187500 40.2250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral