メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.6250000 40.4500000, 141.6312500 40.4500000, 141.6312500 40.4541667, 141.6250000 40.4541667, 141.6250000 40.4500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral