メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.3187500 44.3208334, 143.3250000 44.3208334, 143.3250000 44.3250000, 143.3187500 44.3250000, 143.3187500 44.3208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral