メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.7437500 37.5666667, 138.7500000 37.5666667, 138.7500000 37.5708334, 138.7437500 37.5708334, 138.7437500 37.5666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral