メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8937500 36.0458334, 137.9000000 36.0458334, 137.9000000 36.0500000, 137.8937500 36.0500000, 137.8937500 36.0458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral