メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.3937500 31.8666667, 131.4000000 31.8666667, 131.4000000 31.8708334, 131.3937500 31.8708334, 131.3937500 31.8666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral