メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.3750000 35.4166667, 137.3812500 35.4166667, 137.3812500 35.4208334, 137.3750000 35.4208334, 137.3750000 35.4166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral