メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8687500 36.6958334, 139.8750000 36.6958334, 139.8750000 36.7000000, 139.8687500 36.7000000, 139.8687500 36.6958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral