メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.402217573476 44.1723219875657, 142.400701876431 44.1720752963251, 142.400958994081 44.1712866752907, 142.401747719548 44.1713997404275, 142.402480399922 44.1715047722366, 142.402474321415 44.1715246444361, 142.402419724607 44.1716773565916, 142.402217573476 44.1723219875657)) ^^http://www.opengis.net/ont/geosparql#wktLiteral