メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.1750000 34.7916667, 137.1812500 34.7916667, 137.1812500 34.7958334, 137.1750000 34.7958334, 137.1750000 34.7916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral