メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8125000 36.4875000, 137.8187500 36.4875000, 137.8187500 36.4916667, 137.8125000 36.4916667, 137.8125000 36.4875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral