メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.4000000 44.2541667, 143.4062500 44.2541667, 143.4062500 44.2583333, 143.4000000 44.2583333, 143.4000000 44.2541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral