メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.9875000 42.7208334, 142.9937500 42.7208334, 142.9937500 42.7250000, 142.9875000 42.7250000, 142.9875000 42.7208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral