メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.3187500 43.1791667, 143.3250000 43.1791667, 143.3250000 43.1833333, 143.3187500 43.1833333, 143.3187500 43.1791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral