メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8250000 38.7750000, 139.8312500 38.7750000, 139.8312500 38.7791667, 139.8250000 38.7791667, 139.8250000 38.7750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral