メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.5125000 36.5625000, 138.5187500 36.5625000, 138.5187500 36.5666667, 138.5125000 36.5666667, 138.5125000 36.5625000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral