メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.9250000 39.8250000, 141.9312500 39.8250000, 141.9312500 39.8291667, 141.9250000 39.8291667, 141.9250000 39.8250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral