メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.3125000 36.6291667, 137.3187500 36.6291667, 137.3187500 36.6333333, 137.3125000 36.6333333, 137.3125000 36.6291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral