メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.2937500 31.5500000, 131.3000000 31.5500000, 131.3000000 31.5541667, 131.2937500 31.5541667, 131.2937500 31.5500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral