メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.251040446914 38.0351248936325, 138.251405442969 38.0353709109788, 138.251627825385 38.0355179380254, 138.250991695462 38.0360409990936, 138.250901743456 38.0360336287122, 138.250480653565 38.0359952852949, 138.250821300382 38.0356036500843, 138.251040446914 38.0351248936325)) ^^http://www.opengis.net/ont/geosparql#wktLiteral