メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.9750000 38.3000000, 140.9812500 38.3000000, 140.9812500 38.3041667, 140.9750000 38.3041667, 140.9750000 38.3000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral