メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.0625000 35.2833333, 137.0687500 35.2833333, 137.0687500 35.2875000, 137.0625000 35.2875000, 137.0625000 35.2833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral