メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.4875000 36.9500000, 137.4937500 36.9500000, 137.4937500 36.9541667, 137.4875000 36.9541667, 137.4875000 36.9500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral