メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8187500 44.7250000, 141.8250000 44.7250000, 141.8250000 44.7291667, 141.8187500 44.7291667, 141.8187500 44.7250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral