メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8750000 44.0291667, 141.8812500 44.0291667, 141.8812500 44.0333333, 141.8750000 44.0333333, 141.8750000 44.0291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral