メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.1750000 35.1000000, 137.1812500 35.1000000, 137.1812500 35.1041667, 137.1750000 35.1041667, 137.1750000 35.1000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral