メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.406426685822 44.1640092125977, 142.40322505612 44.1635590385531, 142.403629425466 44.1623028912074, 142.406483066852 44.1627351573962, 142.406513778856 44.1630140814644, 142.406426685822 44.1640092125977)) ^^http://www.opengis.net/ont/geosparql#wktLiteral