メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8250000 36.1958334, 137.8312500 36.1958334, 137.8312500 36.2000000, 137.8250000 36.2000000, 137.8250000 36.1958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral