メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.8937500 36.4041667, 138.9000000 36.4041667, 138.9000000 36.4083333, 138.8937500 36.4083333, 138.8937500 36.4041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral