メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.1250000 43.5416667, 142.1312500 43.5416667, 142.1312500 43.5458334, 142.1250000 43.5458334, 142.1250000 43.5416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral