メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((130.6812500 31.8250000, 130.6875000 31.8250000, 130.6875000 31.8291667, 130.6812500 31.8291667, 130.6812500 31.8250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral