メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.2875000 42.5416667, 143.2937500 42.5416667, 143.2937500 42.5458334, 143.2875000 42.5458334, 143.2875000 42.5416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral