メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.9187500 39.6333333, 141.9250000 39.6333333, 141.9250000 39.6375000, 141.9187500 39.6375000, 141.9187500 39.6333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral