メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.2312500 44.0541667, 145.2375000 44.0541667, 145.2375000 44.0583333, 145.2312500 44.0583333, 145.2312500 44.0541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral