メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.7875000 34.7791667, 137.7937500 34.7791667, 137.7937500 34.7833333, 137.7875000 34.7833333, 137.7875000 34.7791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral