メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.902150341526 43.4678855417853, 141.900245828066 43.4681881709125, 141.899780433442 43.4665894829216, 141.901678367744 43.466264795068, 141.901752186487 43.4665107313729, 141.902150341526 43.4678855417853)) ^^http://www.opengis.net/ont/geosparql#wktLiteral