メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.7687500 44.8416667, 141.7750000 44.8416667, 141.7750000 44.8458334, 141.7687500 44.8458334, 141.7687500 44.8416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral