メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8625000 34.8125000, 137.8687500 34.8125000, 137.8687500 34.8166667, 137.8625000 34.8166667, 137.8625000 34.8125000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral