メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.5937500 36.6125000, 138.6000000 36.6125000, 138.6000000 36.6166667, 138.5937500 36.6166667, 138.5937500 36.6125000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral