メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8750000 34.8416667, 137.8812500 34.8416667, 137.8812500 34.8458334, 137.8750000 34.8458334, 137.8750000 34.8416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral