メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.6687500 43.6208334, 142.6750000 43.6208334, 142.6750000 43.6250000, 142.6687500 43.6250000, 142.6687500 43.6208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral