メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.3125000 38.6250000, 141.3187500 38.6250000, 141.3187500 38.6291667, 141.3125000 38.6291667, 141.3125000 38.6250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral