メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0437500 42.9625000, 142.0500000 42.9625000, 142.0500000 42.9666667, 142.0437500 42.9666667, 142.0437500 42.9625000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral