メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((136.7937500 36.7000000, 136.8000000 36.7000000, 136.8000000 36.7041667, 136.7937500 36.7041667, 136.7937500 36.7000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral