メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.2312500 38.0625000, 138.2375000 38.0625000, 138.2375000 38.0666667, 138.2312500 38.0666667, 138.2312500 38.0625000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral