メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.9500000 39.6000000, 141.9562500 39.6000000, 141.9562500 39.6041667, 141.9500000 39.6041667, 141.9500000 39.6000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral