メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.6875000 43.6125000, 143.6937500 43.6125000, 143.6937500 43.6166667, 143.6875000 43.6166667, 143.6875000 43.6125000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral