メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8812500 35.5500000, 137.8875000 35.5500000, 137.8875000 35.5541667, 137.8812500 35.5541667, 137.8812500 35.5500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral