メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.6875000 32.6416667, 131.6937500 32.6416667, 131.6937500 32.6458334, 131.6875000 32.6458334, 131.6875000 32.6416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral