メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0875000 42.5625000, 142.0937500 42.5625000, 142.0937500 42.5666667, 142.0875000 42.5666667, 142.0875000 42.5625000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral