メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.6500000 42.3208334, 142.6562500 42.3208334, 142.6562500 42.3250000, 142.6500000 42.3250000, 142.6500000 42.3208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral