メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.754339475476 43.1961378056368, 141.753533259813 43.1969515277033, 141.752639639192 43.1964984664908, 141.752609437488 43.1964831444746, 141.753378521499 43.1956555534029, 141.754339475476 43.1961378056368)) ^^http://www.opengis.net/ont/geosparql#wktLiteral