メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8250000 38.2208334, 140.8312500 38.2208334, 140.8312500 38.2250000, 140.8250000 38.2250000, 140.8250000 38.2208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral