メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0937500 38.9083333, 141.1000000 38.9083333, 141.1000000 38.9125000, 141.0937500 38.9125000, 141.0937500 38.9083333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral