メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8875000 34.7708334, 137.8937500 34.7708334, 137.8937500 34.7750000, 137.8875000 34.7750000, 137.8875000 34.7708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral