メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.6812500 43.8708334, 143.6875000 43.8708334, 143.6875000 43.8750000, 143.6812500 43.8750000, 143.6812500 43.8708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral