メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.9000000 32.9375000, 131.9062500 32.9375000, 131.9062500 32.9416667, 131.9000000 32.9416667, 131.9000000 32.9375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral