メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.4000000 36.6416667, 137.4062500 36.6416667, 137.4062500 36.6458334, 137.4000000 36.6458334, 137.4000000 36.6416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral