メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0937500 39.7958334, 141.1000000 39.7958334, 141.1000000 39.8000000, 141.0937500 39.8000000, 141.0937500 39.7958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral