メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.5437500 35.5958334, 138.5500000 35.5958334, 138.5500000 35.6000000, 138.5437500 35.6000000, 138.5437500 35.5958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral