メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8687500 38.2458334, 140.8750000 38.2458334, 140.8750000 38.2500000, 140.8687500 38.2500000, 140.8687500 38.2458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral