メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.2375000 31.9541667, 131.2437500 31.9541667, 131.2437500 31.9583333, 131.2375000 31.9583333, 131.2375000 31.9541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral