メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.3187500 36.7041667, 137.3250000 36.7041667, 137.3250000 36.7083333, 137.3187500 36.7083333, 137.3187500 36.7041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral