メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.43240462688 43.8124327852827, 142.432065164665 43.8127188770288, 142.429454371038 43.8111177732956, 142.430635882696 43.8101324419005, 142.431151540692 43.8104523939417, 142.433228662261 43.8117363226524, 142.43240462688 43.8124327852827)) ^^http://www.opengis.net/ont/geosparql#wktLiteral