メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.0625000 36.6458334, 137.0687500 36.6458334, 137.0687500 36.6500000, 137.0625000 36.6500000, 137.0625000 36.6458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral