メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.2437500 42.4125000, 142.2500000 42.4125000, 142.2500000 42.4166667, 142.2437500 42.4166667, 142.2437500 42.4125000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral