メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.6812500 34.8291667, 137.6875000 34.8291667, 137.6875000 34.8333333, 137.6812500 34.8333333, 137.6812500 34.8291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral