メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.5937500 38.6208334, 139.6000000 38.6208334, 139.6000000 38.6250000, 139.5937500 38.6250000, 139.5937500 38.6208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral