メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.4062500 38.4375000, 141.4125000 38.4375000, 141.4125000 38.4416667, 141.4062500 38.4416667, 141.4062500 38.4375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral