メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.4125000 44.3416667, 142.4187500 44.3416667, 142.4187500 44.3458334, 142.4125000 44.3458334, 142.4125000 44.3416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral