メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.2250000 38.5791667, 141.2312500 38.5791667, 141.2312500 38.5833333, 141.2250000 38.5833333, 141.2250000 38.5791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral