メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.6750000 42.7125000, 143.6812500 42.7125000, 143.6812500 42.7166667, 143.6750000 42.7166667, 143.6750000 42.7125000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral