メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.2875000 38.8833333, 141.2937500 38.8833333, 141.2937500 38.8875000, 141.2875000 38.8875000, 141.2875000 38.8833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral