メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.708586419796 44.3700982858664, 141.708584399069 44.3700995776941, 141.707500608814 44.3707967552708, 141.706390102149 44.3699818199383, 141.706982022336 44.3696114851002, 141.707514510345 44.3692752826602, 141.708586419796 44.3700982858664)) ^^http://www.opengis.net/ont/geosparql#wktLiteral