メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.6687500 43.5541667, 143.6750000 43.5541667, 143.6750000 43.5583333, 143.6687500 43.5583333, 143.6687500 43.5541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral