メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.1250000 43.7250000, 142.1312500 43.7250000, 142.1312500 43.7291667, 142.1250000 43.7291667, 142.1250000 43.7250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral