メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.3000000 38.4166667, 140.3062500 38.4166667, 140.3062500 38.4208334, 140.3000000 38.4208334, 140.3000000 38.4166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral