メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.8437500 42.8416667, 143.8500000 42.8416667, 143.8500000 42.8458334, 143.8437500 42.8458334, 143.8437500 42.8416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral