メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.1250000 42.4208334, 141.1312500 42.4208334, 141.1312500 42.4250000, 141.1250000 42.4250000, 141.1250000 42.4208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral