メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.6687500 35.6041667, 138.6750000 35.6041667, 138.6750000 35.6083333, 138.6687500 35.6083333, 138.6687500 35.6041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral