メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.1562500 35.8958334, 137.1625000 35.8958334, 137.1625000 35.9000000, 137.1562500 35.9000000, 137.1562500 35.8958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral