メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.9812500 36.5541667, 137.9875000 36.5541667, 137.9875000 36.5583333, 137.9812500 36.5583333, 137.9812500 36.5541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral