メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.2437500 35.2916667, 137.2500000 35.2916667, 137.2500000 35.2958334, 137.2437500 35.2958334, 137.2437500 35.2916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral