メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.1750000 40.5500000, 141.1812500 40.5500000, 141.1812500 40.5541667, 141.1750000 40.5541667, 141.1750000 40.5500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral