メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.2125000 38.4833333, 141.2187500 38.4833333, 141.2187500 38.4875000, 141.2125000 38.4875000, 141.2125000 38.4833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral