メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.1187500 38.9250000, 141.1250000 38.9250000, 141.1250000 38.9291667, 141.1187500 38.9291667, 141.1187500 38.9250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral