メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8125000 43.2291667, 141.8187500 43.2291667, 141.8187500 43.2333333, 141.8125000 43.2333333, 141.8125000 43.2291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral