メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5000000 42.6291667, 141.5062500 42.6291667, 141.5062500 42.6333333, 141.5000000 42.6333333, 141.5000000 42.6291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral