メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.3250000 38.1958334, 140.3312500 38.1958334, 140.3312500 38.2000000, 140.3250000 38.2000000, 140.3250000 38.1958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral