メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0187500 38.9208334, 141.0250000 38.9208334, 141.0250000 38.9250000, 141.0187500 38.9250000, 141.0187500 38.9208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral