メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.2375000 35.2791667, 137.2437500 35.2791667, 137.2437500 35.2833333, 137.2375000 35.2833333, 137.2375000 35.2791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral