メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.3875000 44.3083333, 143.3937500 44.3083333, 143.3937500 44.3125000, 143.3875000 44.3125000, 143.3875000 44.3083333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral