メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.5125000 38.7250000, 140.5187500 38.7250000, 140.5187500 38.7291667, 140.5125000 38.7291667, 140.5125000 38.7250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral