メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.4000000 42.9208334, 141.4062500 42.9208334, 141.4062500 42.9250000, 141.4000000 42.9250000, 141.4000000 42.9208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral