メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.3937500 38.3791667, 140.4000000 38.3791667, 140.4000000 38.3833333, 140.3937500 38.3833333, 140.3937500 38.3791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral