メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((130.8937500 31.2958334, 130.9000000 31.2958334, 130.9000000 31.3000000, 130.8937500 31.3000000, 130.8937500 31.2958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral