メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.4000000 38.4625000, 141.4062500 38.4625000, 141.4062500 38.4666667, 141.4000000 38.4666667, 141.4000000 38.4625000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral