メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.3687500 36.7708334, 137.3750000 36.7708334, 137.3750000 36.7750000, 137.3687500 36.7750000, 137.3687500 36.7708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral