メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.3125000 42.1416667, 143.3187500 42.1416667, 143.3187500 42.1458334, 143.3125000 42.1458334, 143.3125000 42.1416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral