メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.4625000 38.1541667, 139.4687500 38.1541667, 139.4687500 38.1583333, 139.4625000 38.1583333, 139.4625000 38.1541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral