メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.5562500 42.2583333, 142.5625000 42.2583333, 142.5625000 42.2625000, 142.5562500 42.2625000, 142.5562500 42.2583333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral