メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5125000 38.8041667, 141.5187500 38.8041667, 141.5187500 38.8083333, 141.5125000 38.8083333, 141.5125000 38.8041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral