メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.7187500 42.7166667, 141.7250000 42.7166667, 141.7250000 42.7208334, 141.7187500 42.7208334, 141.7187500 42.7166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral