メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.404229184877 44.1661943316131, 142.402828078169 44.1662032914248, 142.402717902396 44.1663887591079, 142.402433428236 44.1663373135256, 142.402897467769 44.1648501693586, 142.40327237784 44.1647968262781, 142.404219748403 44.1649391433717, 142.404229184877 44.1661943316131)) ^^http://www.opengis.net/ont/geosparql#wktLiteral