メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.4375000 44.0000000, 142.4437500 44.0000000, 142.4437500 44.0041667, 142.4375000 44.0041667, 142.4375000 44.0000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral