メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0500000 42.9541667, 142.0562500 42.9541667, 142.0562500 42.9583333, 142.0500000 42.9583333, 142.0500000 42.9541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral