メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.0187500 35.1791667, 137.0250000 35.1791667, 137.0250000 35.1833333, 137.0187500 35.1833333, 137.0187500 35.1791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral