メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5500000 38.9000000, 141.5562500 38.9000000, 141.5562500 38.9041667, 141.5500000 38.9041667, 141.5500000 38.9000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral