メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.0687500 35.0791667, 137.0750000 35.0791667, 137.0750000 35.0833333, 137.0687500 35.0833333, 137.0687500 35.0791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral