メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8250000 39.2416667, 141.8312500 39.2416667, 141.8312500 39.2458334, 141.8250000 39.2458334, 141.8250000 39.2416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral