メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.3437500 44.4791667, 142.3500000 44.4791667, 142.3500000 44.4833333, 142.3437500 44.4833333, 142.3437500 44.4791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral