メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.1562500 42.8500000, 142.1625000 42.8500000, 142.1625000 42.8541667, 142.1562500 42.8541667, 142.1562500 42.8500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral