メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8125000 42.7625000, 141.8187500 42.7625000, 141.8187500 42.7666667, 141.8125000 42.7666667, 141.8125000 42.7625000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral