メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.4875000 35.4375000, 137.4937500 35.4375000, 137.4937500 35.4416667, 137.4875000 35.4416667, 137.4875000 35.4375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral