メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.6312500 35.3291667, 138.6375000 35.3291667, 138.6375000 35.3333333, 138.6312500 35.3333333, 138.6312500 35.3291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral