メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8125000 38.8875000, 139.8187500 38.8875000, 139.8187500 38.8916667, 139.8125000 38.8916667, 139.8125000 38.8875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral