メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.5625000 43.2000000, 143.5687500 43.2000000, 143.5687500 43.2041667, 143.5625000 43.2041667, 143.5625000 43.2000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral