メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.1562500 36.6375000, 138.1625000 36.6375000, 138.1625000 36.6416667, 138.1562500 36.6416667, 138.1562500 36.6375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral