メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.4750000 43.4208334, 142.4812500 43.4208334, 142.4812500 43.4250000, 142.4750000 43.4250000, 142.4750000 43.4208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral