メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.3500000 43.8375000, 142.3562500 43.8375000, 142.3562500 43.8416667, 142.3500000 43.8416667, 142.3500000 43.8375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral