メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.4937500 44.0416667, 143.5000000 44.0416667, 143.5000000 44.0458334, 143.4937500 44.0458334, 143.4937500 44.0416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral