メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.4937500 43.2416667, 145.5000000 43.2416667, 145.5000000 43.2458334, 145.4937500 43.2458334, 145.4937500 43.2416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral